Colin Wood's navigational notes



Colin Wood's navigational notes


Notes taken during Colin Wood's training. They cover navigation, wireless, radar, meteorology, intelligence, geography and operations.



IBCC Digital Archive


Anne-Marie Watson
Steve Baldwin


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119 handwritten sheets




Conforms To


[page break]
Swinging a Compass

Can be swung on any cardinal point first but usually on N or S.

1, Check compass for serviceability.
2, Ensure all equipment correct.
3, Place a/ct within 50 of Mag N & note Dev by landing compass. On as site of unusual Mag.
4, Place a/ct heading E & note Dev.
5, Place a/ct heading S & note Dev.
6, Calculate Coeff C by Dev N – S over 2.
7, Correct by changing sign of Coeff & applying to existing reading. Set this against Lubber Line.
8, Insert key in athwartships hole of micro-adjuster & turn until Red is on Red. Compass is now corrected for Coeff C.
9, Carefully remove key
10, Place a/ct on W & note Dev.
11, Calculate Coeff “B” by DEV E – W over 2. & correct as for C. key in F & A hole.
12, Carry out a Check swing on all eight headings starting on NW.
13, Calculate Coeff A & correct if necessary by turning whole compass in mounting requisite number of degrees. Clockwise for positive A & vice versa.
[page break]
Another way is –
Apply Coeff A with sign changed to present compass reading. Set this corrected compass reading. Set this corrected compass reading against the Lubber Line. Loosen screws & turn compass till Red in on Red. Tighten screws.
Calculate Res Dev by applying Coeff A with sign changed to the former DEV’s. Plot a curve of residual devs & draw up a critical point correction cord.
If swing starts on S calculate “C” on N & “B” on E. Do not change sign.

Causes of change of DEV in Flight.

1, Change of bomb load. Cards made out for bombs “on” & bombs “Off”
2, Change in Magnetic Latitude
a, Values of H & Z change with Mag Lat.
b, Dev set up by a/cts mag varies inversely as H.
3, Continuous vibration of a/ct.
4, Operation of Electrical Circuit.
5, Electrical Storms.
6, Engine Speed.
[page break]
Turns [deleted] effe [/deleted] on N & S Mag headings turns effect the compass
On E & W in headings acceleration & decelerations effect the compass.

[underlined] Gyro’s [/underlined]
Distant reading gyro compass.
[underlined] Advantages [/underlined]
1, Overcomes sluggishness due to screening by armour plating.
2, Rid of turning & accelerating errors.
3, Six people in a/ct can have correct reding [sic] at the same time through repeaters
4, Small DEV
5, Readings with no DEV
6, Position of [inserted] repeaters [/inserted] eliminates paralax.[sic]

[underlined] Disadvantages [/underlined]
1, Posn of Master Unit renders it vunerable to enemy action. In tail.
2, If power supply or wires broken compass u/s.
3, Weight.
4, Gyro may topple after evasive action
[page break]
[underlined] Master Unit. [/underlined]

[underlined] Gyro [/underlined]
[deleted] Mag [/deleted]
Rigidity is space
Not N seeking.
Overcomes turning errors
Kept precessing [swic] by needle & contact strip
[underlined] Mag Element [/underlined]

North seeking – keeps [deleted] needle [/deleted] axis at right angles to Mag meridian

First Switch to On
Second Switch to SETTING.
Leave for approx. 5 mins until needle settles to 50 hunt. Then turn to NORMAL.
After evasive action turn to Setting for a few mins & then Normal.
Switch OFF only after a/ct has come to rest.
[underlined] Variation Setting Corrector. [/underlined]
Set on VAR up to 300 E or W & corrects for Coeff A. This give a free reading
[page break]
[underlined] Repeaters [/underlined] (up to 6).
Pilots – for setting Co by movable pointer
Navigators – for reading Co & by putting on Azimuth circle bearings are obtained.
[underlined] Control Panel [/underlined]
Two switch’s ON or OFF & SETTING & NORMAL.
[underlined] Swinging [/underlined] to [underlined] Synchronise [/underlined].
The swing is done by Coeff method with compass running & switched to Normal A swing and then Check Swing.
[underlined] To Correct [/underlined] for [underlined] Coeff A [/underlined].
1, Enter value of Coeff A & date on tablet provided above window of Master Unit cover.
2, On the V[deleted] R [/deleted]SC loosen screws on lubber Ring & set to zero
3, Synchronise all repeaters to read within three degrees of required reading by inserting key in each repeater & turning
4, Turn knob on VSC until repeaters show exact reading
5, Reset loosened Lubber Ring to make scale read zero & tighten screws.
To be done on installation & every eight weeks.
[page break]
[underlined] DR Compass [/underlined]
Synchronising of Repeaters
1, Switch on main switch
2, Place N.S. switch to Setting until repearers begin to function through about 60
3, Place NSS to Normal in centre in Hunt.
4 Set V.S.C. to zero.
[page break]
5, Note the reading on Master Unit & apply Coeff A & obtain corrected reading
6, Set corrected reading on repeater
7, Insert corrector key in centre shaft of repeater & turn both card & pointer until pointer is paralell [sic] to Grid Wires or near as poss
8, Make final, accurate adjustment with V.S.C.
9, Loosen screws holding VSC pointer & reset to zero.
[underlined] Manipulation [/underlined]
1, Switch on DR Compass & with VSC at zero synchronise M.U. & Repeaters
2, Set VAR & DEV on V.S.C.
3, Switch on A.P.I. & allow to warm up for 30 secs.
4, Depress Test Button & lamp should wink regularly.
5, Set Lat & Long of point of depature on counters.
[page break]
6, On take off API will begin to register automatically between above 60 [indecipherable].
7, In flight the API should be reset to a fix approx. every 30 mins.
8, Check synchronisation of MU & Repeaters about every 20 mins.
9, Reset VAR & DEV whenever change occurs.
[page break]
[underlined] Position Lines [/underlined]
(1) By Trasit [sic] +/- 1/20 [symbol] Nearest object first the [indecipherable word] & secont object ie Lightship [symbol] Castle.
(2) [underlined] By Compass Brg. +/- 20 [/underlined]
Obtain compass brg of origin apply [underlined] DEV for a/cts Co(T) [/underlined] then VAR giving true bearing of origin, apply 1800 & lay off [underlined] from [/underlined] origin.

[underlined] Plan Range. [/underlined]
Not very accurate.

[underlined] Relative Bearing +/- 20 [/underlined]
To angle between a/cts head taken as being N 0000 & the line joining obs. & origin measured clockwise 0 to 360.
Add a/cts Co(T) giving T brg of origin.

[underlined] Astro [/underlined]
Within 10 miles.
[underlined] D/F W/T [/underlined]
1st class +/- 20 2nd – +/- 50 3rd – over 50.

[underlined] Uses of Single Posn line. [/underlined]
(1) Aid to Pinpointing.
[page break]
(2) [underlined] To Check G/S [/underlined]
Posn line must cut T at Right angles.
(3) [underlined] To Check Track. [/underlined] M.G.
Posn line paralell [sic] to track confirms track.
(4) [underlined] Homing or Leading Line. [/underlined]
Station sends Q.D.M. which mag co to reach origin.
(a) When Posn line passes through origin a/ct flies up posn line.
(b) When P.L. does not pass through origin
Allow for error & cut P.L. Join nearest cut to destination & fly that T. Draw another T paralell [sic] from other cut. On ETA turn in this case N to destination
[inserted drawing]
[underlined] Cocked Hat. [/underlined]
[page break]
[underlined] Reporting Positions. [/underlined]
(1) Place Names
(2) Lat & Long
(3) Grid System. BC 23 [inserted] (E) [/inserted] 84 [inserted] (N) [/inserted] Kilos
(4) Bearing & Distance.
(5) Lettering Co-ordinates – SW corner first.
(6) Royal Navy Method – Use any corner & give bearing & distance from same corner ie 135 ABMN 30 nm.
Grid variation is angle between N true & Grid N.

Properties of Mercators.

1, Plumb line straight line.
2, Angles are correctly represented
3, Scale varies with Latitude
4, Areas expanded with Latitude
5, Orthormorphic [sic] true to shape.
[page break]
Transferring Posn Lines.

Move Posn line along Track for distance by G/S flown.

W/V by Aid Plot.

DR Posn by Aid Plot.

[underlined] Topographical Maps. [/underlined]

1, Gt Circle [deleted] q [/deleted] approx. straight line Plumb line curved towards Equator.
2, Paralells [sic] curves lines.
3, Convergent St lines (usually)
4, Scale approx. constant.
5, Conformal Angles preserved.
[page break]
[Underlined] Types of Topo Maps. [/underlined]

a, Transverse Mercators Projection.

example – Canadian Air Nav Lines.

b, Lamberts Conformal - Conical.

ie – Aeronautical Charts of U.S.A.

c, Modified Polyconic.

ie RAF 1·500,000

Small Scale 1·1000,000 1-4000,000.
Medium Scale 1·500,000
Large Scale

[Inserted] 1320 YI D/F 215°(T) C.A. NIL.

[Underlined] CON [inserted] V [/inserted] ERGENCY D/F. [/underlined]

Bearing E of origin ADD angle } N HEMISPHERE.
Bearing E of origin SUBTRACT angle } N HEMISPHERE

Convergancy = ch long x sine mean Lat.
=8 x 3sine 30°
=8 x 1/2 = 4°.

Conversion angle = 1/2 convergancy.


[Page break]

Refined Procedure for Plotting D/F Brgs.


1, Obtain D/F brg.
2, Find DR Long & calculate CA.
3, Apply CA to brg to obtain RL. Draw in RL.
4, Where RL cuts nearest DR Long line draw a tangent to GC by applying CA again to RL
Use when CA is greater than 5°.


[Underlined] Loop Bearings [/underlined]

[Calculations and graphs]

[Page break]

[Calculations and graphs]

[Underlined] C of Equal Bearing. [/underlined]

Is a curve along which the true GC of a stn from an [deleted] d [/deleted] a/ct is always the same.


To the reverse of the Co apply PLUS twice drift if this has been to STARBOARD, or, MINUS twice DRIFT, if this has been to PORT.

PORT – MINUS twice DRIFT to Co


[Page break]

[Underlined] Gnomonic Projection. [/underlined]

1, Paralells [sic] as concentric circles } POLAR
2, Long lines converging at the Pole }
3, Scale is exaggerated away from Pole.
4, Gt circles Straight lines.
5, RL or curved concave to Pole.
6, Shapes & angles distorted.


[Underlined] Equatorial [/underlined]

1, Meridians st Lines.
Farther apart away from point of convergancy
2, Paralells [sic] concentric curves to Equator.
3, Scale not constant.
4, Gt Circles st lines.
5, GIL curves convex to Equator.

[Underlined] Oblique [/underlined]

1, Paralell [sic] at P of Tang is a st line
2, Meridians at P of T st lines.
3, Paralells [sic] converge at P of Tang.
4, St lines converging toward Pole [deleted] of T. [/deleted]
5, Gt Circle St line
6, RL concave to Pole.
7, Angles & areas wrong.


[Page break]

Transferring Posn lines by Proportion.


Measure AX to any scale
Draw AB as near track as possible or use Co.

[Calculation & Diagram]

Along Co join Air Posn to Posn line with any W/V – 60 K is best as there is 1nm per -min. From second Air Posn lay in W/V to second Posn line for another 10mins & transfer Posn line through meeting point

[Page break]


Mark on rule to any scale first 3 units & then 5 units the other way from a zero point. Lay [inserted] rule [/inserted] on 3 posn lines until all three points on rule are above or on posn lines.

[Diagram inserted]

Lay in a line in approx. direction of Track & from centre where middle Posn line cuts it at mark 3 units & 5 units in proper direction. From these points join to 1st & 3rd Posn lines by line paralell [sic] to 2nd Posn L.

[Page break]

[Diagram inserted]

Join Fix to Posn where 2nd & 3rd lines are taken from for you must have been on this line. This makes third Posn so use Unit Method to find TMG. & then transfer this through the Fix. This gives TMG & G/S so Air Posn & join to FIX at 1930 & find W/V.

[Underlined] Critical Point. [/underlined]

1, Algebraically
2, Graphically
3, Computer.

[Diagram and calculations]

[Page break]


WH = Reduced TAS for 1 hr
WO = Reduced TAS for 1 hr
X = Any point along AB.
XW = W/V for 1 hr
HX = G/S home
OX = G/S Out.
A-Hx = Hx
Hx – ox = xo
Ox – B = Line joining these two.
Hx – P = Line parallel [sic] to OX-B.


by setting H on outer scale against H+O on inner scale the C.P. will be found opposite total distance measured on inner scale.

[Page break]

[Diagram and calculations]

Drift & Wind Lane

1, Take a Drift
2, Take brg on Wind Lane.
3, Set Drift on Computer
4, Discard one of the values of the Wind Lanes.
5, Allowing for veer compute the W/V

e.g. Wind Lanes 130/310.
TAS 120K
Ht 500’
Drift 108
Co 000

[Page break]

Angle between TRACK & wind direction Is [sic] always less than 90°

[Underlined] TAIL [/underlined] If wind angle is greater than 180 but less than 270 subtract from it 180

If wind angle is greater than [number missing] but greater than 180 subtract from 180

[Underlined] HEAD [/underlined] If wind angle is less than [number missing] but less than [number missing] leave

If wind angle is greater than 180 but less than 360 subtract from 360.

Factor Divide TAS by W/S.

To find Co given TRACK W/V

1, Find Factor
2, Divide Factor into sixty this will give MAX drift for prevailing beam wind. 3, Obtain wind angle.
4, Whatever fraction this wind angle is of 90, take same fraction of drift [underlined] oft[/underlined]tained [sic] in section 2,
Determine P or S.
Apply reverse to get Co.

e.g.W/V 310/20 TR 170 TAS 120

1, Factor 6
2, Max Drift 10
3, Wind Angle 40
4, Drift 4 8

[Page break]

To Find G/S

1, Wind Angle between [Calculations & diagram]

[Underlined] Leading Lines [/underlined]

Calculation of Co to make good LL & TTT knowing direction to turn & having one leading line & [right angle symbol] s to present Co & not having any W/V.

From centre Air Posn & radius Air Distance describe an arc to cut Posn line Cut on [deleted] on [/deleted] right if you want to turn Port from point which this arc cuts P.L. to Air Posn. This line is then Co to steer to make good LL

Prove – LL equals required track
Air Posn to LL equals wind effect

[Page break]

Co line mentioned above represents Air Speed for similar length of time for which the wind has been effecting you.
angle ؞between Co line & PL equals Drift
؞ Co line equals Co to make good LL


Extend present Co until it cuts LL
Measure distance from Air Posn to PL & add or [inserted] subtract [/inserted] to Air Distance. Measure distance from PL to LL


When X = time to run to LL.

General –

If after an appropriate time of flight the reliable PL is obtained not at [right angle symbol]’s to Track it would then be possible to turn until it is at right angles to Track, transfer this PL by proportion (on wind effect) & use this transferred PL with which to follow out steps above.

If the Nav has no certainty of his posn he may turn to such a Co that a definite direction of turn to make good this LL will be insured. Not forgetting that the PL must be at [right angle symbol]’s to present Track.

[Page break]

Winds & TAS on Climb & Glide.

Computing TAS for Climb

In working out DR Posn for a long climb or calculating EAD before-hand it is nessecary [sic]to allow for changes in TAS which is constantly changing to alteration of height.

[Underlined] Method [/underlined]

If the lower height add 2/3 of difference between lower & upper hts. Use the ht thus obtained for conversion of RAS to TAS, the resultant TAS will then be used as the average for the whole climb.

[Underlined] Example [/underlined]

2000’ to 17000’ climb.

To 2000’ add 2/3 difference of 2*17000.
17000’ – 2000’ =15000’ [divided by sign] 3x2 = 10000’+ 2 =12000’

[Page break]

Instructions for Log-Keeping.

1, Nothing entered in log which has not a definite brg on navigation Entries relating to a/ct equipment other than nav equ: not responsible by nav [sic]: not entered.
2, Nothing is to be entered into the body of log which has a column for it
3, Time Ht Temp & TAS are to be recorded on each occasion when setting Co altering Co climbing descending or levelling out [sic] & [underlined] whenever a fix is obtained [/underlined].
4, W/Vs should always be followed by the method by which they are obtained & for what ht & must occupy seperate [sic] lines.
5, Times of OR Compass ON & OFF Compasses checked & SBA checked must be entered in the log.
6, Degree mins & Ditto marks never to be used.
7, QFE from Base [deleted] from [/deleted] must be logged – A SL Pressure

[Page break]

8, Lat & Long for DR Posns Air Posns & Fixes should not be shown in the log. Should be entered with time as FIX DR
9, Air Posn Indicator reading over Base when setting Co & on return should be logged
10, The amount added or subtracted to the Lat & Long to the API reading when resetting should be logged against the fix & time at which it is reset
11, The API reading over the target is to be logged.

[Underlined] Chartwork [/underlined]

1, When preparing charts all T Ps, Concentration Points & posn’s of Track Markers to be lettered & referred to by the letter in the log.
2, Time must be marked against every symbol.

[Symbols for A.P., D.R. and FIX].

[Page break]

Logging Loop Brgs.

D/F Loop “A” Sc Rdg 157 QC -2 Rel Brg 155

CoT 340 ؞ GCB 135 CA +2 RLB 137

Log Marking.


1, The objective
2, The claimed posn
3, The plotted posn by photo
4, The plotted posn by analysis
5, The intended destination & ETA
6, The actual point of arrival &ETA.

To what extent were the following maintained

a, Log
b, DR Plot

Was full use made of the following if not – reasons

a, Visual fix
b, Astro
c, Loop
d, M/F D/F
e, H/F D/F
f, Flying Control
g, night lights organisation

[Page break]


In addition to the [word missing] there is a mag field due to the capacity effect between aerial & ground that is the [word missing] that is of importance in direction finding. The lectric [sic] field is only to conserve energy of mag field, the latter being the one which sets up in the receiving aerial the same frequency as in transmitting aerial.

An aerial is a conductor connected to a radio receiver or trans which can be used to transmit & receive radio signals. An electric current passing thro a conductor produces a mag field around it & a conductor in a varying field carries an alternating current this is theory of aerials.

A current in trans aerial & hence in wave itself may be interrupted or modulated either by voice morse etc, these interruptors [sic] are compressed upon wave & are reproduced in current induced in rec: aerial by mag: field of wave.

[Page break]

[Underlined] Wave Motion. [/underlined]

A wave is a disturbance propogated [sic] in any medium in such a manner that the shape but not nescesarily [sic] the magnitude of disturbance is repeated at regular intervals in space & time.

The passage of such a disturbance thro medium is termed [underlined] wave propogation [sic] [/underlined]

[Underlined] Properties of a Wave. [/underlined]

[Underlined] Velocity [/underlined] – The velocities of propogation [sic] is the vel with which the energy of the wave is conveyed from point to point in medium.

[Underlined] Frequency [/underlined] Number of complete cycles of disturbance which pass a given point in one second. A Cycle [deleted] s [/deleted] is one complete series of varyations [sic] of displacements between adjacent repetitions of the wave in space.

[Underlined] Amplitude [/underlined] – Is peak value for max displacement of the medium from its normal position.

[Underlined] Wave Length [/underlined] Is distance between corresponding states of displacements in two adjacent repetitions of the wave form.

[Underlined] Wave Propogation, [/underlined] From the transmitting aerial wave are propagated in all directions some travel paralell [sic] to earth surface but are rapidly absorbed by the surrounding objects & earth itself. The range of that ground wave depend [sic] on power of transmitter, the

[Page break]

frequency of radiation, nature of ground & season of year. Other waves are propagated skyways & are called sky-waves.

Low frequency waves are radiated skywards to a lesser degree than H.F. waves & are sometimes called flag-waves. They are of course best for D.F. but since they are much more rapidly attenuated than H.F. waves the latter are also used for D.F. work.



Reception of radio wave by straight wire aerials. If one is erected in path of radio wave & connected radio receiver it will be energised by wave. Mag field of wave will cut aerial & induce in it an alternating current which is exact replica of the transmitting aerial current. Function of receiver is ؞ simply to reflect the particular wave or station & convert resultant current into an audible signal.

Polar Diagram of Intensity

Straight wave aerial has no directional properties – omnidirectional.


Reception of Radio Waves.

Are straight interconnected aerials. (Loop). The bulk of directional finding is carried out by use of aerial systems

[Page break]

which depend for their directive properties of straight spaced aerials the volts of which are combaned [sic] as suitable receiving circuits

Directional Properties of Loop Aerial.

End on, different current is induced in each limb causing a circuit to form & giving a signal. MAX


Broadside on, both limbs are cut by same part of the wave & exactly similar voltages induced & no current will flow round loop. MIN.


[Page break]

[Underlined] Notes [/underlined] from [Underlined] Graph. [/underlined]

1, The loop has 2 MAX & 2 MIN signal strength posns in 360°
2, MIN positions more clealy [sic] defined than MAX as there is a bigger change in strength for a smaller amount of turn.

[Underlined] Figure of Eight or Loop Diagram. [/underlined]


A co-sign diagram gives two MIN & two MAX. The direction of a transmitting station may ؞ be derived with 180° ambiguity. MIN positions used in practice because of their more sharply defined nature.

This 180° ambiguity may be derived by sense by combining open & loop aerial.

Determining Sense using Sense Aerial.

1, Take a loop brg & note time
2, Rotate loop 90°
3, Tune in station using sense aerial & adjust till signal is [deleted] m [/deleted] same strength as

[Page break]

signal received on Loop.
4, Operate Loop reversing switch to determine if original bearing was correct or recipical [sic].


D/F Loop.

1st – minimum covers from 0° - 5°
2nd 6° - 15°
3rd 16° - 30°

Ground D/F

1st minimum covers from 0 - 4°
2nd 5 - 10°
3rd over 10.

[Underlined] Coastal Refraction [/underlined]


[Page break]

① MAX Dev on N & S. Of opposite sign
② No Dev on E & W but loss or gain of directional force.

COEFF “C” = DEV on N – DEV on S [divided by] 2.

[Underlined] Co-eff A [/underlined]

1 Real “A”. Combination of horizontal sub-divided soft iron mag which gives same Dev on all headings. 1/2° limit

Apparent “A” – Due to compass being offset from F & A axis of a/ct – reading incorrectly by same amount on all headings.

Co-eff A – corrected by rotating whole compass in its mounting the same no of ° as calculated Coeff.

Clockwise for +ve A
Anticlockwise for -ve A

Coeff A = DEV on [inserted] MAG [/inserted] N +NE + E + SE + S + SW + W + NW [divided by] 8

[Underlined] Micro Adjuster [/underlined]

Two pairs of bar magnets mounted on crown wheels & may be opened or shut by a key. These can control

[Page break]

mag in line with that of a/cts major components. Stronger mag when like Roles brought closer together. [sic]

[Underlined] Standard Procedure for Compass Swing [/underlined]

By Coeff Method.

1 Check compass for serviceability
2, Ensure all equipment not carried in flight is removed & other equipment correctly stowed.
3, Take a/ct to place of unusual mag:
4, Controls in flying position.
5, Place a/ct N & note Dev by landing compass.
6, Place a/ct E & note Dev by landing compass.
7, Place a/ct S & note Dev by landing compass.
8, Calculate Coeff C by DEV N-S over 2.
9, If correcting determine new compass reading as follows – Change the sign of Coeff & apply it to existing compass reading Set this against L.L.
10, Insert key in athwartships hole & turn till Red on Red. Now corrected for Coeff C.
11, Place a/ct heading W & note Dev
12, Calculate “B” by Dev E-W over 2 & correct as for “C”. Key in F & A hole.

[Page break]

[Underlined] Night Effect. [/underlined]


Upper atmosphere more completely ironised [sic] by sun than lower. Mostly at Dusk & Dawn a clear-cut layer of ironised [sic] air is formed. Also at night. Has property of reflecting wirless [sic] waves travelling towards it back to earth.

These reflected waves may cut horizontal components of loop & induce unwanted voltage in them. May destroy MIN signal

[Underlined] Quadrantal Error. [/underlined]


Re-radiated fields set up by wireless waves striking masses of metal in fuselage & wings. Resultant is in Q.C. This causes apparent bending of waves (as received by loop) which is at MAX from Quadrantal points. If greatest mass of metal in F & A axis bending towards F & A line. (Twins)

If in athwartships bending towards that (4en}

1, Note sign of QC & error is apposite. QE varies with frequency

[Page break]

In some streamlined housings energised coils can be adjusted to reduce MAX to ± 4°

Sharpens zero signal.

Only fixed by skilled engineers.

[Underlined] Calibration of Loop. [/underlined]

Should be carried out

1, When loop installed in a/ct.
2, On structural modification
3, On addition of magnetic apparatus or subtraction
4, After every three months
5, After electrical storms.

[Underlined] Methods [/underlined]

1, Prepare a/cts for swing-compass-check equipment -radio.
2, Select known M/F transmitter 50-100 miles away & ascertain it will be transmitting for duration of swing
3, Measure (T) or MAG Great Circle brg of stm.
4, Take a/ct to suitable site away from any mag disturbances – electrical, runways etc.
5, Set a/ct in flying posn – loop not screened.
6, By means of Landing or Astro Compass swing a/ct through 360° taking brgs every 10° of stn.
7, Add brg to a/ct heading & compare with known GC bearing of Xmitter. Difference is QE, change sign for QC.
8, Construct a graph of QE plotting

[Page break]

errors against loop reading
9, Prepare Correction Card.

Range of Communications

1, Power of transmitter & sensitivity of receiver.
2, Ht of a/ct. Higher the better range.
3, Frequency – HF generally greater range.
4, Atmospheric & electrical disturbances (thunderstorms)
5, With H/F – time of day – greater range at night.
6, Intervening country. Best over sea & further over moist than dry land.

Route Marked, Equi-signal or Radio Range.

Between 200-400 KC.

6210 KC 3105 KC R/T. Call up stn & ask for weather report.


In 3° margin continous [sic] signal is heard.

In 60° margin one is heard louder than the other

In 27° margin only one is heard

Stn call sign every 45 secs or so

[Page break]

[Underlined] Uses [/underlined]

1, Fly the beam.
2, Take D/F LOST BRg.
3, Take time of crossing beam & take centre time of coming out & posn line is in centre. Angle on map.

[Deleted] Range of [/deleted]

Rotating Beacon.

Flying Control

[Underlined] Functions [/underlined]

1, To give assistance on demand to any a/ct requiring aid.
2, To assist a/ct to land at and given station or stations as required by the pilot or op staff.
3, To enable a/ct to be diverted to other stations when their own base becomes unfit. [inserted] 24hr service – [/inserted]

[Underlined] Frequencies of F.C. [/underlined]

1, A/ct guard & safety Frequ.
[Deleted] 2, [/deleted] D/F & control Frequ.
2, 2 H/F D/F channels.
3, Emergency R/|T. {DARKY call-sign).
W/T – wireless telegraphy
4. SBA.
5, 1 VH/F D/F channel (Fighters)

[Page break]

Facilities available from F.C. Stn.

1, Weather Reports or changes in weather
2, Reports on station of landing ground.
3, Request for landing lights & flame paths.
4, Radio assisted & control approach (Descent thro’ cloud [sic]
5, Standard Beam Approach.
6, Homing Bearings & Co s to steer
8, [sic] Full assistance after an SOS.

Central Flying Control.

[Underlined] Functions [/underlined]

1, To advise Bomber Group Comma[inserted] n [/inserted] ders on the availability of alternate aerodromes should the necessity for large scale diversions be foreseen.
2, To co-ordinate the effort of the Groups so as to make best use of alternative dromes.
3, To advise & co-ordinate diversion during ops.

[Underlined] Group F.C. [/underlined]

[Underlined] Functions [/underlined]

1, To assist the Group operational staff in the control of their a/ct during operations.
2, To have ready any information required by Group op staff when necessity for diversion occurs.

[Page break]

Flying Control Stn Type I

① A/ct Guard & safety Freq.
[Deleted] 2, [/deleted] [Underlined] Facilities [/underlined]

1, Weather Reports ①
2, Reports on state of landing ground. ①
3, Request for flare paths & landing lights. ①
4, Diversions to other airports are also given ①
5, Request for S.B.A.
6, Request for R.A.C.A.

② D/F & Control Freq.

2 H/F D/F channels
1 V/HF D/F (for fighter a/ct). ②

1, Homing bearings. – QDM QUJ ②
2, Co s to steer ②
3, Radio assisted & controlled approach.
4, D/F bearings 100 miles
5, D/F brgs to 500 miles (-under certain conditions)

③ Emergency Distress R/T (DARKY).

[Underlined] Distress Procedure. [/underlined]

1, Switch on I.F.F. 100 miles from Coast (Start 3)
2, Fire coloured lights on crossing coast
3, If over 100 miles contact M/F D/F.
4, Contact any other M/F D/F station
SOS (3 times) UAB (3) ABCD 1234 (3) SOS AUB (3)

C – Course.
H – Height
D – DR POSN [inserted] & TIME OF POSN [/inserted]

[Page break]

[Underlined] LIGHTS [/underlined]

F – A steady continuous light
FL – Sending out a flash at regular intervals
Occ – Sending flashes of darkness (longer light time than darkness) at definite intervals.
Alt – alternating – changing colour at definite inter
[Deleted] Gp [/deleted] F.FL. – Fixed & Flashing.
G.P. – Fixed number or group of flashs. [sic]
[Deleted] F.FL – [/deleted]
REV – Revolving. Increases to MAX or decrease to Occ or eclipse.
U. Unwatched – unreliable.

[Underlined] Factors Effecting Visibility [/underlined]

1, Met Conditions
2, Refraction
3, Ht of Observer
4, Ht of Tide


Lock loop athwartships & turn a/ct till MIN heard. Take B.B. & offset loop scale by same amount. Fly down MIN until over station.

First make sure which side station is on. Signals increasing stn on Starboard. Signals decreasing stn on Port.

[Page break]

Fixed Beacon.

No directional properties.

Directional Beacons.

1, A Beam
2, A Rotating Beam

Single D/F

Posn line


Ground D/F FIX
Bearing & Dist.
Same as Single.


2-300 miles Ranges.

Procedure for Obtaining Fix.

Call up stn & identify yourself.
Give Priority.

Classification of [deledted] Fixes [/deleted] [inserted] Brgs. [/inserted] by Ground D/F.

[Table of Classifiaction of Fixes]

[Page break]

[Deleted] Fixes [/deleted]

[Underlined] X Code [/underlined]

X663. Bearing of you was – class – at –
X687 Send your call sign & 5 second dashes to enable brgs to be obtained.
X696 My Co to reach you – zero wind.
x699 Reply to QDM.
X700 True brg from you.
X702 What is my posn or fix.
X704 What is my posn by D/F brgs.
X709 CoT to reach you using Zero wind.
X711 (Reply to X709) at (time)
X714 Reply to X704) [sic]
X671 Cannot plot your posn.

[Underlined] Q Code [/underlined]

QBA – Horizontal visibility
QBB – Vertical visibility [inserted] Ht of [inserted] base of [/inserted] cloud at – [/inserted]
QAA – What is ETA
QAM – What is latest met Report
QDM – What is my Mag Track to reach you. [inserted] with zero wind. [/inserted]
QDR – Reciprocal to QDM [inserted]. Your mag brg in relation [inserted] to me is – [/inserted] [/inserted]
QTE – What is true bearing in relation to you
QFF – Barometric pressure at MSL
QDL – Do you intend to ask for
[Inserted] QFE Barometric pressure at ALP at – [/inserted]

[Page break]

a series of QDMs.
QFS – Please place radio beacon at – in operation
QGA – May I land using the Beam Approach
QBG – You may not land with B.A.
QGH – May I have a descent thro cloud
QGI – You may not
QFM – What is the ht to fly
QFG – You are over D/F hut
QST – Change frequency to a certain number of kilo.c.
QGE – What is my posn in terms of true brg & distance.
[Inserted] QDY – Same as QDM but B Barrage [underlined] within [/underlined] 60 miles of [inserted] me on that track [/inserted] [/inserted]

[Underlined] British Beacons. [/underlined]

[Inserted] QTF – Position of you’re a/ct accding [sic] to brgs taken is –

Mobile & Splashers.

Three stns keep changing round & take turns at sending. Times are secret so enemy cannot take bearings.

Splashers are three stns working together & enemy does not know which to jam.

[Underlined] Counter Measures [/underlined]

1, Jamming.
2, Meaconing. Enemy stn sends

[Page break]

same signal & Nil cannot be found. Or fills in silence so steady signal is heard.

Standard Beam Approach.

Belini – Tosi.

Search Coil


Underground wires covered & so secure from Night Effect.


7G7 – Gt Group from N Ireland.
7Z7 – Jurby. I of Man.
UU7 – Loch Erne.

Identification must be made on M/F D/F.

1, Crossing coast below 2000’
2, If returning early
3, When you make landfall other than that which you briefed for (40 miles)
4, When IFF is U/S
5, When shadowed by enemy a/ct.

[Page break]

Wireless Theory.

[Underlined] Priorities. [/underlined]

1, Most Immediate. O -U

Application – messages of vital importance & only to be used in times of strained relations or war. Authority – Members of Air Council only. Outside Air Ministry – Air Officers Commanding in Chief or officers commanding independent commands.
Time Limit – Immediate.

2, Emergency – Enemy Aircraft. O – A.

Application – reporting of enemy a/ct
Authority – Air or other officers commanding & delegated to anyone whose duty it is to report enemy a/ct. Immediate.

3, Emergency. O.

Application – Operation [sic] messages of vital importance. Used in war or warlike local [deleted] l [/deleted] ops. Authority – Staff officers not below W.C or C.O. of a unit. May be delegated Formation Leader [sic] or captain of an a/ct acting singly. 15 mins time limit.

4, Immediate. O -P.

Application – For messages of extreme importance & of less importance than the above. Staff of headquarters not below rank od W.C. C.O. of a unit, formation leader. & same as no 3. Time limit 30 mins.

[Page break]

5, Important P.

Application – Messages which are important but not sufficient to justify Immediate but which need precedence over ordinary messages. Relate to - troop movement - weather reports & request.
Authority - HQ officer not below S.L. CO of a unit adjutant or duty Pilot & captain of a/ct acting singly. Time limit 45 mins.

Advantages & Disadvantages of W/T.

1, Independent of surrounding country.
2, Greater range
3, Speed.
4, Signals may be received at several points at the same time.
5, Portable
6, Suitable to a/ct.


1, Interseption. [sic]
2, Divulges position of transmitting station or a/ct.
3, Liable to interferance [sic] from other stations & weather.

[Page break]

1, [Underlined] Employment of Armed Forces. [/underlined]

2, [Underlined] War. – Means of Avoiding. [/underlined]

a, Diplomacy
b, Propaganda.
c, Economic Pressure.

2, [Underlined] War [/underlined]

1, Armed Forces
2, Man-power.
3, Economic System
4, Finance
5, Morale.

[Underlined] Role of Navy [/underlined] is Offensive.

a, Attack enemy shipping fleet
b, Defensive. – Protection of own shipping.

[Underlined] Role of Army. [/underlined]

a, Offensive – Destroy enemy army occupy & dominate territory.
b, Defensive – Protection of home territory & overseas possessions.

[Underlined] Role of Air Force. [/underlined]

a, Attack of enemy
b, Defensive against air attack.

[Underlined] Air Warfare. [/underlined]

[Underlined] Characteristics [/underlined]

1, Range.

[Page break]

a, Deep penetration enemy country.
b, Long over-sea patrols.
c, Rapid

2. [Underlined] Speed [/underlined]
a, Less time over enemy territory.
b, Avoids enemy fighters.
c, In fighters – Tactical advantage – more efficient interception.

3, [Underlined] Flexibility [/underlined]
a, Independent of terrain.
b, Dont [sic] need to be concentrated on ground.
c, Changeable functions.

4, [Underlined] Mobility. [/underlined]
5, [Underlined] Power of Evasion. [/underlined]

[Underlined] CONDUCT OF AIR WARFARE [/underlined]

1, [Underlined] The Air Striking Force. [/underlined]
a, Public utilities service.
b, Industrial centres.
c, Military Naval & Air establishments.
d, Stocks of food, raw materials & goods

2, [Underlined] The Defence force. [/underlined]

3, [Underlined] Naval Co-operation Force. [/underlined]
a, Coastal Command.
b, Air Branch R.N.
c Fleet Air Arm.

[Page break]

[Underlined] Procedure. [/underlined]

A.A.A. Full stop. or indicates Plain Language to follow.
IMI - Repeat.
N. – Nothing heard. --.--
BT – In Preamble – Code or Cypher to follow if at the end of text. Indicates message completed & T O.O. to follow.
VE Commence sign.
AR Ending sign. All transmission regarding messages have been completed.
II Seperation [sic] sign.
AA Unknown stn call sign.
IMIWB Word before.
IMIWA Word after.
IMIAB All before.
GR Groups
HM HM HM HM HM – W/T silence to be maintained.
WO WO WO WO WO – Cease W/T silence.
SOS SOS SOS International Distress Call.
C – Correct.
G – Repeat back.
R – Received.
AS – Wait.
K – Go ahead

[Page break]

F – Not to be answered.
V – From
H – Counting number of groups.

VE R08 R08 V L4Q K Preliminary Call.
VE L4Q V R08 K Answers preliminary Call
VE R08 V L4Q NR1st - Priority R G R 10 – AAA

31/8/43. Ten ansons departed Winnipeg 1040 eta Rivers 1140 – 0939 K.

VE L49 V R08 R. AR. or maybe TMT K. or TMT WB ansons.


Over – My transmission is ended & I expect a reply from you
Out – Conversation ended & no reply expected.

Component Parts of R/T Message.

I Call
II Text
III Ending.

[Underlined] U.S. & British Priorities. [/underlined]

[Deleted] Urgent [/deleted] [underlined] US British [/underlined]

Urgent Emergency.
Ops Priority Immediate.
Priority Important

[Page break]

Time – 1440. Not T.O.O.

R/T Procedure Phrases.

[Underlined] Roger [/underlined] – I have received all of your last transmission.
[Underlined] Acknowlegde [sic] [/underlined] – Let me know if you have received & understood.

[Underlined] Willco [/underlined] - Your last message understood & where applicable will be done.
How do you hear me.
Speak slower.
Wait. – I must pause for a few secs.
[Deleted] I [/deleted] Await Out – pause longer than a few secs.
Say again – Repeat.
I say again – I will repeat.
Verify – check coding & text with originator & send correct version.
Message for you – I wish to transmit a message to you.
Send your message – I am ready for transmission
Read back – Repeat all message back exactly as received after I have given “over”
That is correct – You are correct.
Words twice – As a request – Communication difficult please send each group twice.
- As Information – groups will be sent twice.
Correction – An error has been made in this transmission, correct version is. –

[Page break]

Wrong – What you have just sent is incorrect, the correct version is –
Groups - No of Groups or cipher is –

Hello. Dono this is Jane. Message for You. Over.

[Underlined] Visual [/underlined]

{Aldis Lamp.
{Identification Light
Flags – International Code of Flags.
Flag Waving.

W – Unable to read you owing to bad light
LL. – Light is to [sic] powerful - dimi [deleted]she[/deleted]nish.
MH. - Move higher or farther away
ML – Move to your left.
MR – Move to your right.
MA – Use -F . method
OL – Open the light. To align lamp on.
[Underlined] VE [/underlined] – General call sign.
VA – All transmissions completed.

[Page break]

To Make out a Message.

1, Address.
2, Addressee.
3, Originators [sic] Number & Date.
4, In reply to & Date.
5, Text.
6, Originators [sic] instructions
7, Priority
8, T.O.O.

Signal Duties of a Navigators [sic].

1, Synchronise Watches with WAG. & Pilot.
2, Initiate requests for Brgs.
3, When Loop is used stns should be told where stns are used.
4, Inform WAG when you use D/F.
5, Show Pilot MTB’s
6, Warns Pilots.
7, Items to repair Radio equipment.
Careful Stowage

[Deleted] G [/deleted]

[Underlined] 1155 [/underlined]

Tuning Dial – semi-circular & corresponds to range colouring.
Frequency Band Switch – Mode of OPS.

[Page break]

5 [Indecipherable word]

1, OMNI for all-round.
2, AVC – Intended for R/T
3, BALANCE – for visual D/F.
VIUAL – for visual D/F.
EIGHT- Aural D/F.

Volume Control – Increase or decrease.
Hetrodine Switch – for reception of code.
Hetrodine Adjustment – varies the pitch. when receiving code
Filter – switch on to reduce interference.
Meter Amplitude – to control visual needles.
Meter Balance Switch – to balance needles before taking bearings.
Meter Deflection Switch – High for VISUAL LOW for Homing & Aural.
Switch Speed Control
HIGH for code
LOW for [missing word]
Aural Sense. Acts as brg recipical [sic] switch for aural D/F.

To tune in Signal.

1, Turn switch on transmitter to STANDBY
2, Mode of operation switch to OMNI
3, Place band switch to proposed band.
4, Tune signal using tuning control first coarse then fine.

[Page break]

5, Advance volume to proper signal strength.
Filter may be used to avoid interference

[Underlined] Aural D/F [/underlined]

Tune in
Meter Deflection Switch to Low.
Figure of 8 Posn & turn loop until Min signal is heard.
Check sense by decreasing scale reading
If signal is louder with switch on R than L, reading is on scale. [Deleted] L [/deleted] If L loudest, scale reading is recipical [sic].

[Underlined] Visual D/F. [/underlined]

Tune in station.
Deflection Switch on High
Switch Speed – Low for R/T, High for Code.
Mode of OPs switch to Balance, adjust intersection needles by Meter Balance Switch.
Adjust Meter Amplitude for a high intersection of needles to [deleted] give [/deleted] Max sensitivity.
Mode of OPs to Visual
Turn loop until needles intersect on line. & note reading & time
Decrease Scale reading & if needles fall to R reading is right & if to L recipical [sic].

[Page break]

Homing by Visual Meter.

Items the same but Meter Deflection Swtich to Low (not so [deleted] be [/deleted] Lively)
Set Loop to 000 on scale (athwartships to a/cts head).
Turn a/ct until until [sic] needles intersect after determining Sense which is checked every 10 minutes.

[Underlined] TR 9 D. [/underlined]

Old Fighter receiver transmitter combined Two Channels or Frequencies.

1, Aerodrom [sic] Control
2, Darky for approx. pinpoints.
3, Inter comm between members of crew.
4, Inter comm between formations of a/ct.
5, Squeakers. (Balloon Barrage).
1333 Dinghy Transmission

Transmitter & Loading Coil.

[Underlined] 1154 [/underlined]

Trailing & Fixed Aerial.

OP & Earth switch. Put on E during electrical storms & earths to frame of a/ct & cuts out high-tension.

[Page break]

Ranges of Operations

1, 200K to 500Kc. – Yellow
2, 3m.c to 5.5 m.c – Red
3, 5.5m.c. to 10 m.c. – Blue

[Underlined] Precautions [/underlined]

1, Carefull [sic] stowage.
2, Prevention of damage by shock.
3, Prevention of damage by water
4, Testing of instrument cords while in use.
5, Period inspection by electrical engineers.

[Underlined] Nav Precautions. [/underlined]

Synchronise watches
Initiates request for loop brgs.
Guide to best stations.
When D/F used W/O should be informed which stations should give best fix
Makes MTBs.
Informs Pilot whenever Drift’s D/F Astro is being taken.

Dog Easy Fox
George How Item
Jig King Love
Mike None Oboe
Peter Queen Roger
Sugar Tare Uncle
Victor William X Ray
Yoke Zebra.

[Page break]

[Underlined] RADAR [/underlined]

[Underlined] IFF – To provide identification to ground that you are friendly a/ct.
Used for Distress.

1, Switch On.
2, Note that M.A. reads between .6 & 2 M.A.
3, Volt meter should read 12 volts. Adjust by Volume control
4, Ensure that Code Switch is to No 1
5, Plug in phones & listen to background of clicks. If occalations [sic] are heard adjust Tuning Screws A1 A2 & B by turning fully Anti-clockwise & then turning A1 to first occolation point

[Page break]

& then turning 3 clicks back.

For Distress turn Code Switch to No 3.



1, Switch On.
2, Ensure Code Switch is always at No 1
3, See that N is showing under spring loaded flap
4, Plug in & listen for clicks.
5, For Distress turn wheel & move N until D is showing.
6, No emergency [sic] can be taken if Set occilates [sic].

[Page break]

Testing for I.F.F.

Apply volt meter or Aldis Lamp across two points of plug & note there is no reading

[Underlined] Dinghy XMitter. [/underlined] - T 1333.

500 Kc/s. Listening in periods are from 15 – 20 mins & 45 – 50 mins past the hour.

Range of a Kite aerial is 150 miles
Range of a Mast aerial is 20 miles.

300 volts High tension } by generator.
6 volts Low tension} 5 WATS [sic]

Two positions – Hand & Automatic.

[Deleted] M/F D/F [/deleted]

[Underlined] Loop Beacons. [/underlined]

“A” Group situated [deleted y [/deleted] in Yorkshire
“B” Group situated in Norfolk
”C” Group situated in Lincolnshire.
“D” Group situated in Yorkshire
“F” Group situated in Cornwall
“J” Group situated in Aberdeenshire
“G” Group situated in N Ireland.

[Page break]

Gives 24 Hr service.
A three mast Group.

“G” Group marked ABC – all others 1.2.3.

Jurby 7 Z 7 Lock [sic] Earn U U 7
Prestwick Barra Hd
Butt of Lewis.

[Page break]


Atmosphere & changes that take place in it.

Information Available.

1, Local Weather [underlined] Report. [/underlined]
a, Surface Winds & Cloud.

2, Clouds.
a Type of middle & high cloud.
b Low Cloud – Type. Ht above [underlined] ground [/underlined]

3, Vis – Horizontal.

4, Weather
Weather at time of observation.

2, [Underlined] Forecast [/underlined].

3, Icing Report

a, Location of icing zone
b, Temp.
c, Thickness of cloud.
d, Ht of cloud above ground

Synoptic Chart.

A map on which is plotted the weather so a birds-eye view at a certain time can be obtained.

[Page break]

[Underlined] Pressure [/underlined]

New – Barometer

Station Pressure { 1, Index Error.
{2, Latitude & Centigraph Force
{3, [deleted] S [/deleted] Temp
4, Altitude

Dew Point. –

Is temp at which air must be cooled & constant press before condensation begins

Wet Bulb Temp.

Is temp to which air can be cooled by evaporating water into it assuming press remains constant

Relative Humidity

The amount of water vapour actually in air [divided by] Amount of WV needed to saturate same amount X 100

[Underlined] Upper Air Data. [/underlined]

1, Aeroplane ascent

Meteograph {Baragraph
2, Radiosonde.

[Page break]


1, Type.
2, General Appearance
3, Sequence.
4, Cu Heaviest to East than West

Value of Cloud Recognition.

a, Above cloud approach.
b, In cloud
c, Evasive action.

Continuity. Bumpiness.
Icing Visibility.
Vertical Thickness. Ht of base above ground.

Altocumulus Castillatis [sic]. Vis 120 yds.

May mean thunderstorms later on.
Moderate Bumpiness. Severe if it turns to C.B.

1, Troposphere 7-8 miles.
5/6 of air by weight.
Vertical Currents.
Water Vapour.
Temp decreases with ht a 3°F per 1000’.

2, Stratosphere.
Little overhead motion
Almost no water vapour.
Temp remains constant with ht.

[Page break]

3, Tropopause.
Variations in ht.
1, Latitude
Equator – 11 miles above ground
N. Pole – 5 miles above ground
2, Season
Higher in Summer than in Winter.

[Underlined] Composition. [/underlined]

1, Constant –

Nitrogen, Oxygen

2, Variable –

Water Vapour.
Solid particles ie smoke, salt, pollen & dust.

[Underlined] Pressure [/underlined]

1, Average change with ht.
Decrease of 1mb per 30’
2, Variations from average

[Underlined] Winds. [/underlined]

1, Pressure Gradient.

Is rate of change of pressure measured perpendiculary [sic] to the Isobars.

2, Winds about a Low at 2,000’ or Geostrophic Level.

Blow Anti-clockwise & paralell to Isobars at a speed measured from the Geostrophic Wind Scale.

[Page break]

3, Winds above Geostrophic Level.

To W backs to W } Gain in Speed.
S veers to W }
E backs or veers to W }
With Low over N Pole & High over Equator.

Surface Winds

1, Normal case 2, Variation
Turbulence or Gustiness.
due to friction. Due to unequal heating of earths [sic] surface.

[Underlined] Gust [/underlined] – Sudden increase in speed & change in direction of the wind lasting one to two minutes

[Underlined] Diurnal Variation [/underlined]

Due to transfer of momentum from Geostrophic to Surface level, surface wind veers & increases during day. Back & decrease at night.

[Underlined] Squall [/underlined] Same as Gust but lasts longer – 5 or 6 mins. Due to Cold Front or Thunderstorm.

[Underlined] Due to Topogrphy. [sic]. [/underlined]

1, Barrier Effect.
2, Tunnel or Tunnel Effect.
3, Valley Effect.
4, Land & Sea Breezes.
5, Katabatic & Anabatic.
6, Chinook or John. [sic]

[Page break]

[Underlined] Polar Front Theory. [/underlined]

[Underlined] Bjerknes.. [/underlined]

1, [Underlined] Air Mass. [/underlined]

A huge revolving mass of air with uniform properties of Temp & Humidity in a horizontal direction.

2, [Underlined] Source Region. [/underlined]

a, Temp of surface is uniform.
b, Pressure system should be a HIGH.

[Underlined] Gt Britain. [/underlined]

1, North Atlantic
2, Northern Russia.
3, Bermuda or Azores.
4, Sahara.

An Air Mass will move & as they move are modified.

Vertical Currents.

Rising air always cools at a rate of 5.4°F due to expansion – Adiabatic Cooling Dry
Dry Adiabatic Lapse Rate 5.4° per 1000’.

When Environment L R is less than D A L R air is stable vertical currents will not develop

When E.L.R. is [deleted] less [/deleted] [inserted] MORE [/inserted] that D A L R air is unstable & vertical air currents will develop.

[Page break]


[Underlined] Vertical Currents [/underlined]

1, Orographic Features & other obstructions.

(a) Strength of Wind.
b, Stability of Air.
c, Nature of ground.

2, Surface Heating

[Page break]

[Underlined] Heating of Earths [sic] Surface. [/underlined]

1, [Underlined] Radiation. [/underlined]

Heated from below.
Greenhouse Effect.


2, [Underlined] Conduction [/underlined]
3, Convection.

[Underlined] Subsidence. [/underlined]

Air sinking in middle of air mass & meeting air which is rising from ground causing Compressibility & maybe warmth hence an Inversion. [Inserted diagram]

[Underlined] Humidity & Cloud Formation. [/underlined]

[Underlined] Humidity [/underlined]

1, Absolute Humidity is weight of water vapour in 1 Cu metre of air.
2, Wet Bulb Temperature.
3, Dew Point.

[Underlined] Condensation. [/underlined]

1, Cooling.
2, High R Humidity.
3, Condensation nuclei. – pollen, salt, smoke.

[Page break]

[Underlined] Causes for Condensation. [/underlined]

1, Warm Air moving over cold surface. dew or Hoar frost.
2, Mixing
3, Radiation Cooling.
4, Adiabatic cooling.

a, Turbulence. S.C.
b, Convection. Cu Cb.
c, Orograpic lifting. Sr or Cu Cb.
d, Frontal.

[Underlined] Precipitation. [/underlined]

An appreciable deposit of condensed W/V in either the solid or liquid form.

Types -

1, Thermal Convection precip:
Cu –
Cb – heavy to moderate showers.

2, Orographic.
ST – drizzle.
Cb – heavy to Mod showers.

3, Frontal
AS Light
Nb – becoming moderate [inserted] 200 miles. [/inserted] continuous precip.

[Page break]

[Underlined] Precipitation. [ /underlined]

[Underlined] Snow [/underlined] It forms at at [sic] temp below freezing point where ice crystals are formed, these grow & falls [sic] as snow if temp [deleted] if [/deleted] is below FP all the way down.

[Underlined] -Hail. [/underlined]

Consists of hard pellets formed by raindrops being caught by swift ascending currents & air & carried up far above FL & freeze. Move about & grow by collision with super-cooled drops. Cb cloud.


Continuous Rain – Green Shading
Intermitent [sic] Rain – Green Hatching.
Showers – Green Triangle
Drizzle – Green Commas.

[Underlined] Visibiity [/underlined]

Is greatest distance at which prominent objects can be recognised against the horizon with naked eye.

[Page break]

[Underlined] Code [/underlined] [Drawn circle]

Plotted on Circle in Red in [underlined] Code [/underlined]

[Underlined] Restrictions [/underlined]

1, Condensed Water Vapour.
a, Clouds – [underlined] average [/underlined] 220yds.
Least in low rainbearing clouds.

2, Precipitation
a, Rain. Moderate about 2 1/2 miles
In Heavy 1100yds.
b, Drizzle – Poor.
c, Snow – Zero or very bad.
d, Fog – from zero to 1100 yds.
e, Mist – from 1100 to 2200 yds.

- [Underlined] Fog [/underlined]

[Underlined] Radiation. [/underlined]

a, High R H.
b, Clear Skies
c, Light wind – 8 mph.
d, No Dram-off.

[Underlined] Advection. [/underlined] - Horizontal motion.

Warm moist air and moving over a cold surface.
Example – Tropical Air Mass – Maritime from Azores or Bermuda – passing over English Channel in Spring & summer.

[Page break]

Hill or Upslope Fog.
Steam Fog.
Frontal Fog

Air slides into Trough of Low & starts to rise, cools & forms fog. Mixing at Frontal Surface will lower down & form Fog.


Smoke & Dust.

1, Dust
a, Characteristics of Region
1, Dry
2, Little vegetation
3, Light soil.

b, Conditions in Air Mass.
Unstable Air

2, Smoke.
a, Industrial smoke.
Condition of Air Mass
a, [sic] An Inversion.
Surface heating will help to break through Inversion & allow Fog to escape. Strengthening of wind.

[Page break]

3, [Underlined] Haze [/underlined]
a, Solid Particles.

[Underlined] Icing [/underlined]

1, Dangers associated.
a, Increase air drag
b, Increase stalling speed

2, Fixed wing tip slot

3, Motor Efficiency
a, Carbu: icing (60°F)

4, Airscrew icing.

5, Jamming of controls

6, Mis: - Pitot Head. Radio. Doors.

Physical Processes of Formation

a, Clear Air.
1, Carb icing (60°F)
Ventilation Effect
Evaporation of Petrol.
[deleted] b [/deleted] 2, Sublimation.
Water vapour to ice crystals

b, [Underlined] Cloud [/underlined]
1, Small well super-cooled droplets. Large piece of opaque ice which does not adhere to a/ct & small amount of water

[Page break]

which adheres to a/ct as clear ice
2, Large slightly supercooled droplets. Small piece of opaque ice & a great amount of water which adheres to a/ct as clear ice.

c, Freezing Rain.
Temp slightly below freezing.

[Underlined] Hoar Frost [/underlined]

Part of a/ct effected:

Entire machine coated.

[Underlined] Situation [/underlined] Cold a/ct enters warm moist air eg: descent.
[Underlined] Effect [/underlined] Radio. Windscreen
Take-off impossible.

[Underlined] Rime Frost [/underlined]

Leading Edges.
Thin cloud composed of small super-cooled droplets.
Changes shape of airframe
Pitot head. Carb:

[Underlined] Glaze & Clear. [/underlined]

Leading Edges
Ram slightly below F.P.
All effects.

[Page break]

Opaque & Transparent.

Leading Edge.
Thick clouds composed of large slightly [inserted] super [/inserted] cooled droplets
All Effects.

In layer cloud 33°F to 14°F. 3°F per 1000’.
= 6 000’ zone
In heap 32°F to -4°F
= 1200’ zone.
Rain – just below 32°F

1, Ht Flight.
2, Fronts


[Page break]

1, Freezing Rain (Frontal [sic]
a, Land
b, Turn back

2, Cloud
Cu = Avoid
Sc = above – go up through gaps

[Underlined] Thunderstorms. [/underlined]

a, High R.H.
b, Unstable air to high levels.

2, [Underlined] Characteristics of Cb. [/underlined]


3, [Underlined] Types [/underlined]

a, . [Underlined] Surface heating [/underlined] (Air Mass)

1, Diurnal heating.
1, Late afternoon, persisting into the night
2, Spring or Summer
3, Local

[Page break]

2, Air moving over a warmer [inserted] water [/inserted] surface
1, NW wind over warm Atlantic Drift (winter)
2, NE wind over warm N Sea (Winter)
3, Mediterranean Sea (winter) – violent.

3, Air moving over a warmer land surface.
1, Summer
2, Daytime.

4, Orographic.

b, [Underlined] Frontal [/underlined]

1, Cold Front

2, Warm Front
a, Ahead of Front, higher base & not so violent

3, Occlusion.

[Underlined] Dangers. [/underlined]

1, Bumpiness – 10-15 000’
Over mountains 18 – 20 000
2, Hail – Structural damage.
3, Icing – glaze
4, Light[deleted]e [/deleted] ning – radio.

[Page break]


1, Conditions Necessary.

Pressure Systems
1, High Pressure
2, Col
3, Trough – Front
4 Trough – with no Front
5, Secondary Low – Summer.

[Underlined] Pressure Systems [/underlined]

1, [Underlined] High [/underlined]

A, [Underlined] Summer. [/underlined]
1, Light winds. Isobars wider apart near centre
2, Clear Skies – due to subsidence, sinking of air disperses cloud
3, Inversion. – by compression.
4, Cumulus or cb – surface heating.
5, Fog

B, [Underlined] Winter [/underlined]
1, 10/10 Sc is possible.
Convergance. [sic]

[Underlined] Ridge [/underlined]

Weather same as High
Very brief as it is between two Lows.

[Page break]

[Underlined] Low [/underlined]

Convergance [sic] giving rising currents.

[Underlined] Trough. [/underlined]


[Underlined] Secondary Low. [/underlined]

a, Summer – shallow
b, Winter – deep
Gales – heavy rain.

[Underlined] Line Squall [/underlined]

Rapidly moving cold front


When Tropical Maritime Air reaches England in spring or Summer. Usually is very stable & may form War & Cold Front.

[Page break]


Gives Cold Front behind which will be Cu & Cb, - near the Low will be Cb heavy, & in front will be Sc & occational [sic] Cb.

[Underlined] Weather Maps. [/underlined]

1, Speed of the Front.
2, Time Front will pass your stn.
Find what –
Winds will do
Weather – clouds. precip:

[Page break]

[Underlined] Ship Recognition. [/underlined]

[Underlined] Importance [/underlined]

1, Recognise enemy ships & take appropriate action.
2, Recognise allied ships
3, Ability to accurately report to Intelligence Branch.

What to Report.

1, Nationality.
2, Type
3, Tonnage.

Types of Bows.

1, Straight Bow. [Right angle sign] to Deck & Waterline
2, Raked Bow. Inclined back to Waterline
3, Clipper Bow. Concaved back to Waterline
4, Maser Bow. Convexed back to Waterline
5, Ram Bow Foot strengthened & protruding

[Drawings of Bows]

[Page break]

[Underlined] Types of Stern. [/underlined]

1, Counter Stern


2, Cruiser Stern


3, Cruiser Spoon


4, Square


5, Tuggy


[Underlined] HULLS. [/underlined]

1, Flush Decker

2, Flush Decker with well deck
a, Well Deck F’ward
b, Well Deck Aft

3, Three Island
a, Three Island with engine aft.

4, Gram & Ore deck.

[Page break]

Flush Deck.


Flush Deck with Well deck f’ward.


Well Deck Aft.


Three Island.


Engine Aft.


Gram & Ore.


[Underlined] SUPERSTRUCTURES. [/underlined]

1, Full.
2, Composite
3, Spilt.

[Page break]

[Underlined] Extreme Full. [/underlined]

At least two almost full length of ship.
Queen Mary


[Underlined] Moderate Full. [/underlined]

Athlone [inserted] Castle [/inserted]. One only full ships [sic] length & any number of other decks.


Minor Full.

Any number not full length of ship. More than 2 decks. New York.


[Underlined] Composite [/underlined]

One deck joined to bridge with one funnel on it. Maid of Kent.


[Underlined] Split. [/underlined] (freighters).

Bridgework separated from superstructure.


[Underlined] MAST. [/underlined]

1, Pole
2, Tripod
3, Goal Posts
4, Samson or King.

[Page break]

Pole Mast.


[Underlined] Tripod. [/underlined]

2 supporting legs. Either will support main mast
naval vessels.


[Underlined] Goal Post [/underlined]


[Underlined] Samson or King [/underlined]


Naming of Masts.

F.O. mast – single usually forward
Mainmast – another mast added.
Mizzenmast – 3rd added.
Jiggermast – 4th.
Spanker - 5th – sailing vessels.

[Underlined] Duties of Intelligence Section. [/underlined]

1, To collect was [sic] & culrevate [sic] information.
2, To deduce a true picture from that information
3, To distribute the true facts to proper quarters,
4, To prevent enemy obtaining information of us.

[Underlined] S.I.O. Duties [/underlined]

1, To pass onto Air Crews authentic information of enemy defences targets etc.
2, To allocate any particular job of reconnaisence [sic] to crews.

[Page break]

3, To collect & curelate [sic] information collected by Air Crews & pass on to Command Intelligence
4, To organise & control the Intelligence library so Air Crews may keep up to date with their information.

[Underlined] Sources of Intelligence Information. [/underlined]

1, Neutral & enemy press & radio
2, Examination of captured docks [sic] & equipment.
3, Innterragtion [sic] of prisoners.
4, Reports from secret agents.
5, Naval Military & Air reconasense [sic].

Reconacence [sic] consists of obtaining information about enemy & the ground of his occupation by means of observation & reporting same to base.

[Underlined] Rules [/underlined]

1, On all occasion flying over enemy territory on which he may be operating crews should carry out recon
2, Make brief clear notes in Nav Log of all points of interest observed.
3, Crews should report only what they see.
4, Crews should not make deductions or use guesswork.
5, Observation should where possible be confirmed with photo’s. Be accurate.

[Page break]

[Underlined] Value of Photo [/underlined]

A photo records all detail permantly [sic] & accurately [sic].

[Underlined] Advantages of Air Reco. [/underlined]

1, Speed & range of a/ct allows observation of a large area in a relatively short time.
2, A/ct can use cloud cover to obtain surprise secrecy & security.
3, A/ct can surmount natural barriers & enemy land defences.
4, Ht of a/ct gives VIS.

[Underlined] Limitations of Air Reco [/underlined]

1, Adverse weather can interfere [deleted] of [/deleted] or prevent.
2, Enemy defences may hamper it.
3, Identification of Army or Naval units is difficult.
4, Negative information is unreliable as a/ct cannot force action from a hidden enemy.
5, Camaflouge [sic] or deception can fool crews.

[Underlined] Rule for Reports. [/underlined]

1, Always give place time & ht from which each observation is made.
2, Indicate posn by one of approved methods

[Page break]

The Four Natural Divisions.

1, Scandinavian [inserted] 8,000’ [/inserted] Highlands pass across N Sea – Pennine Chain – Cambrians.
2, Southern [deleted] Islands [/deleted] Highlands – Pyranees [sic] [inserted] 10,000’ [/inserted] Alps [inserted] 2000 [/inserted] & Carpathians
3, Ayberian [sic], Italian & Balkan Peninsulas Cantabrians Appenines Dineric Balkan Mts
Sierra de Quadanranna [sic]. Mt Etna 10,000’. Pindus
3, The Great Plain.
Runs from Southern Highlands to Arctic Ocean. From Urals to Caspian on East Atlantic on West.
4, Plane [sic] of Hungary


[Underlined] Rivers of Europe. [/underlined]

Source in Alps.

1, DANUBE – East to Black Sea.
2, RHINE – North to N Sea
3, RHONE – South to Med.
4, PO – S & E to Adriatic.

[Page break]

Source in Great Plane [sic].

1, Over [sic], Vistula N to Baltic S.
2, Elbe Weser Rhine – N to N Sea.
3, Seine – English C.
4, Loire, Daronne [sic] – B of Biscay.
5, Dneiper, Dneister [sic] into Black
6, Don into Sea of Azov.
7, Volga Caspian.

[Underlined] Islands. [/underlined] Bodies of Water.

1, Lofotens.
2, White Sea
3, Fairoe Islands [sic]
4, Gulf of Finland & Bothnia.
5, Baltic Sea.
6, North Sea
7, Scaggerak & Katterjat [sic]
8, Jutland Peninsula.
9, Gib.
10, Gulf of Lions & Genoa.
11, Tyrhenian [sic] Sea.
12, [Deleted] Alfatic [/deleted] Alfians [sic]
13, Dardanelles, Sea of Marmoro, Straits of Bosphoros

[Page break]

[Underlined] British Isles. [/underlined]

Mountains – Grampiens – Penine [sic] Chains Cambrians.

Rivers – Thames, Severn, Trent, Clyde, Mercy [sic] Tyne.
Bristol Channel, Carnigan [sic] Bay, St Georges Bay, North Channel, Irish Sea, Solway Morry [sic] Pentland Firths, Firth of Forth & Clyde The Wash.

Islands –
Shetlands Orkney Man Wight & Scilly.

Aberdeen Dublin Belfast Brum Bristol Cardiff Coventry Dover Dundee Edinburgh Glasgow Hull Leeds Leicester Liverpool Manchester Newcastle Norich [sic] Nottingham Plymouth Portsmouth Sheffield Southampton Swansea Londonerry [sic]

[Underlined] France [/underlined]

Mountains –
Pyronees [sic] Alps Gulf of Lions [sic]

Dunkirk Calais Lille Dieppe Le Havre Rouen Paris Naney [sic] Cherbourg Brest Marseille Toulon Lymes [sic]

[Underlined] Italy [/underlined]

Appenines [sic] Gulf of Genoa River Po & Tiber Liberian Sea. Catoma [sic] Syracuse Brittonia [sic]

[Page break]

Paloma Marsella. Messina.
Regio Naples Rome Genoa Turin Milan Venice

Augsburg – MEs.
Berlin – Administration & Communication Centre
Bremen – Focke Wolfe & Sea Port
Cologne – Ford Moters [sic]
Cuschaven – U-Boats
Desseu – Junkers.
Dortmund – Steel. & Canals.
Dresden – Optical instruments
Duisberg – Inland Port & Industry
Dusseldorf – Tube works. Communications.
Emden – Sea Port & iron imports.
Essen – Krupps
Frankfurt-on-the-Marne – Cars chemicals
Friddrishschen [sic] – Dorniers.
Hamburg – Sea port & shipyards a/ct factories.
Hamm – Railway centre
Gena – Brass works & optical instruments
Kessel – a/ct & Locomotive Factories.
Kiel – Canal & Shipyards.
Leipzig - Engineering & chemicals.
Lubeck – Ship-building.
Mannhein – Chemicals communications engineering
Munster – Railway Centre.
Munich – Engineering & a/ct engines.
Narenburg – Heavy vehicles & tools

[Page break]

P Tilson – Skoda.
Rostock – Seaport dockyard & Heinkels
Saarbrucken – Coal & Iron.
Stettin – Sea Port, chemicals & oils.
Stuttgart – Bosch Magnetic works & engines.
Wilhelmshaven – Naval Base.

[Underlined] Reports from Air. [/underlined]

1, Time, Ht, & place & visibility.
2, Your Posn. 090-x-2’
3, Show N.
4, Detail – rails, roads (1st & 2nd) bridges dams. Rivers.
5, Large buildings. Nearby aerodromes.
6, Activity – rail & road. Populace.
7, Terrain. Method of attack. Best targets.

[Underlined] Italy [/underlined]

Brindisi Foggia Taranto. Salerno Leghorn. Florence. La Speza. Genoa Milan Turin Trieste Terune. Split.


Corsica. – Bistea.

[Underlined] Med Islands [/underlined]

Balearic Isles – Marjerka & Melerna [sic] Corsica Sardinia Pantelleria Malta Scily [sic] Capri.

[Page break]



Principle of ASI is a relationship of two pressures – pressure – of and outside a/ct against pressure inside.


[Page break]

[Underlined] ERRORS. [/underlined]

1, Position & Attitude
2, Density – a, Temperature
b, Pressure – height.
3, Mechanical Error.

Position – due to position of Pressure Head.
Must be in undisturbed air.
Altitude – due to angle of a/ct to flight path.
Density – temp & press changes. Can be corrected on computer.
Mechanical Error. Due to imperfections in instrument
Other errors due to Leakages, dirt

[Underlined] Altimeter Setting. [/underlined]

Airport pressure reduced to M.S.L. in ICAN scale.

[Underlined] Correction for Temp. [/underlined]

Set ht above ground opposite temp.
Isothermal – Subtract {add} 2’ per 1,000 indicated for every 1°F that the mean temp is below (above) 50°F
ICAN – Subtract 10% of indicated Alt for every 28FC & that actual temp is below ICAN temp for that ht.
Also Compensator Bar.

[Page break]

[Underlined] C.S.B.S. [/underlined]

Uses – 1, To produce accurate line of sight for bombing purposes.
2, To obtain Drift.
3, To find W/V.

1, Warn Pilot. 2, Level.
3, Set TAS to MIN. 4, W/S to MAX
5, T/V to Infinity.
6, Enemy speed to zero & direction at 90 or 270
7, Clamp Bearing Plate. With eye at backsight Keep head still & manipulate D wires so that objects on ground appear to run along them for their full length. ؞ D wires are aligned with Track & angle between them & F & A axis is Drift.
Read drift on Drift scale against Wind Scale bar

Take several in bumpy weather
Notify Pilot.

[Underlined] To Check Course. [/underlined]

1, Line up D wires with natural P.L.
2, Read off angle measured by D Wires.
3, If D Wires are to S’board subtract angle from true brg of P.L. to get Co(T)

[Page break]

[Underlined] To Check G/S. [/underlined]

1, Warn pilot.
2, Find Drift & set on.
3, Set computed ht above ground on Red ht scale.
4, With eye at backsight time the passage of objects along D Wires & between sets of beads Take average of several.
5, This gives number of secs to cover 1 mile or number of mins to cover 60 miles.
G/S can be worked out from this. Time must be within 1/5 sec.

[Page break]

[Underlined] TIME. [/underlined]


Conversion – Arc to time – divide degrees, min°secs by 15.
Time to Arc – Multiply hours, mins & secs by 15.

Watch Keeping.


[Page break]


[Page break]


Moons revolution [deleted] l [/deleted] round earth takes 28 days. About 13° per day.

[Underlined] Sub-Stellar Point. [/underlined]

A point on surface of earth through which passes a line joining a heavenly body to centre of earth.

[Underlined] Declination of a body [/underlined]

Equivalent to Lat of S.S.Pt. of body. Measured No5 from Equators (Terrestrial & Celestial).

[Underlined] Local Hour Angle [/underlined]

Change of Long between some standard meridian [deleted] (GM) [/deleted] & that of the body always measured clockwise thro’ 360° from standard meridian.

[Underlined] Greenwich Hour Angle [/underlined]

Measured from GM to Body westwards.

Complement of angle measured – X60 – is distance of observer from S.S.P.

[Page break]




[Page break]

Star Recognition.

Heavenly panorama changes with respect to us as it revolves around POLARIS, but position of stars relative to one another does not change.

1, Stars
2, Sun – a star the centre of our universe
3, Moon – satelite [sic] of EARTH, completes orbit in 28 days.
4, Planets – posn relative to us changes continually
- shine by reflected light.
- stars twinkle – planets don’t.

[ Diagrams]

[Page break]


[Page break]

Estimating Range.

Man fills 2/3 of blade foresight at 600 standing
Man fills 2/3 of blade foresight at 400
Man fills 2/3 of blade foresight at 250 kneeling.


Ensure gun is unloaded.
Remove bolt
Clean bore using 4 x 4 1/2 flanelette
Pour [underlined] boiling [/underlined] water through barrel from breach end.
Dry & lightly oil the barrel.
Clean & oil magazine.


[Page break


Smoke Cloud Navigation
Flame Flash Navigation
Aluminium Sea Marker.
Flare Reco: 4.5”
Photographic Flash 4.5”
Signal Distance Marine.
Cartridge Signal 1.5”

Signal Rocket 1 lb

[Page break]

[Table showing different pyrotechnics, uses & storage]

[Page break]


[Page break]

Accessories for Mirror Photography.

1, Modified Type 25 mount.
2, 8” Lens Cone.
3, Mirror placed at 45° angle to axess of lense [sic].
4, High speed Types 35 Control (2 sec TI).
5, High speed gear box (rewind in 2 secs).
6, High speed Shutter around 1/1,000’ sec.
Type 35 Control is switched on with releasing of Bomb Switch.
Mirror photo: is used to photo the results of low level & dive-bombing attacks.

[Underlined] Filters [/underlined]

A 25 (RED) - minus Blue (Yellow).

[Underlined] Purpose [/underlined] - 1, to increase contrast
2, Penatrate [sic] haze.
3, Help to detect camouflauge. [sic]
[Deleted] For [/deleted] 4 For normal colour correction & contrast minus blue is used & for extreme use A25.

[Page break]


[Page break]


Smoke Generator – Percussion – kept in stores. [inserted] ground to a/ct. [/inserted]

#5 – Friction. Remove striker from Cd & draw across scratch card.

#6 Aircraft to ground – kept in a/ct – percussion.
Remove safety pin & drop overboard
Smoke Puffs – for finding W/V. Carried in a/ct.
Percussion. Fired from signal pistol.

600yds. Limiting Range.
400yds - Effective Range
150yds – Point . Blank.

10’ per 100 yds
40’ group at 200 yds = 2 RADs full.
40’ group at 400 yds = 1 RAD.

Flare Framing Reconnassance [sic]. 4”

Use – Ground illumination - for forced landing & night photography.

Precautions – 1, Ensure Safety Pin pulled before take-off.
Ignited by friction by means of pull percussion ignitor.
2, Ensure Static Cord is fastened to carrier or a/ct.

[Page break]

Flashes Photographic. 4” Mk I

Use – In conjunction with camera to photo bomb bursts. (timed with shutter of camera by means of photoelectric cell.).
Carried on L/S carrier.
Percussion by means of [deleted] 484 [/deleted] 848 or 849 fuse with specified delay capsule.
Ensure that proper delay capsule is in fuse & screwed properly into base of flare.
Precaution – Do not touch rubber band around fuse body. Ensure fuse does not become dismantled.

[Page break]

[Diagram of Type 35 Control]

[Page break]

Green light indicates that the power is reaching the camera & a contact is made in camera. It goes on when camera released & stays on till camera fully wound.

Green light burns cont:
Red light at regular intervals

[Underlined] Camera Running [/underlined]
Causes – 1, Faulty Time Switch in Control.
2, Brocken [sic] spring on Locking Lever.
3, Push-Button stuck in Control

Camera break down

Causes – +, Brocken [sic] or faulty.
1, Flexible Drive.
2, Motor.
3, No 4 Lead.

[Underlined] Hand Held Obliques. [/underlined]

Any photo taken at an oblique angle approx. 45°
Type 21 Mount used.
Lens must not face into Sun.
Camera must be level.

[Page break]

13, Carry out check swing on all 8 headings.
14, Calculate “A” & correct if neccecary [sic] by turning compass in mounting Clockwise for +ve A & vice versa.
Must have Nav officers [sic] permission.

[Underlined] Testing Compass on Unsuitable Site. [/underlined]

From extreme edges of estimated area of swinging ground take two brgs by landing compass of some clear object 3-4 miles away & if they differ by more than 1° site unsuitable.

Then take brg of object & bring a/cts compass over exact spot & note heading by P-4. Then take brg which will be from true heading of a/ct & note diff between this & landing com: brg.

L.C. Mag: Headg = Mag Brg of object +(360 - Relative Brg)
M:H: = M:B + 360 – RB.

[Underlined] Test for Serviceability. [/underlined]

1, Examine external paint work for corrosion.

[Page break]

2, Test freedom of Grid Ring.
3, Test locking device.
4, Internal paint for flaking & liquid for discolouration & bubbles.
5, Suspension of Compass bowl.
6, Test for Pivot Friction.
7, Damping Test. –
Deflect mag system 90° & hold for 1 min.
Release & time its [sic] swing back through first 85°. Times in Instrument Manual.

[Underlined] Astro Compass [/underlined]

Checking Co by Heavenly Bodies.

1, Level carefully.
2, Warn the pilot.
3, Calculate LHA & DEC of body.
4, Set LHA & Dec & D.R. Lattitude. (all to nearest degree).
5, Turn [deleted] cop [/deleted] complete top of instrument until body is in line of sight. (Use Pin Shadow for Sun.[sic]
6. Read Co(T) against L.L. on bearing plate.

CO EFF “C” is algeebaic [sic] value of the Dev: on magnetic N caused by component Q & its allied soft iron effects




Colin Wood, “Colin Wood's navigational notes,” IBCC Digital Archive, accessed February 18, 2020,

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