British Pathfinder Operations as
at March 1944
Issued by Luftwaffenfuhrungsstab
The success of a large-scale night raid by the RAF
is in increasing measure dependent on the conscientious flying of
the Pathfinder crews. The frictionless functioning of the attack is
only possible when the turning points on the inward and courses, as
well as the target itself, are properly marked. Lately, these
attacks have been compressed into about 4 minutes for each wave
averaging 120-150 aircraft
Dense and high reaching clouds, which hide the sky
markers over the target, and exceptionally strong winds which blow
the markers away quickly, represent an unpredictable barrier to
Pathfinder operations and can often appreciably decrease the
efficiency of an attack.
Another reason for the failure of a raid may lie in
the partial failure of the first Pathfinders, the 'Initial Markers',
to arrive, since experience has shown that succeeding Pathfinders,
in spite of being equipped with H2S and blind marking equipment,
have allowed themselves to be influenced, to a certain extent, by
the Initial Markers.
1. The concentrated
large-scale RAF raid on Cologne on 30/31 May 1942, during a full
moon night and with an alleged strength of more than 900 aircraft,
was the first attempt to imitate the 'Focal Point' raids initiated
by the German Air Force during this strategic air war against the
British Isles during the years 1940 and 1941.
The lessons taught by this first large-scale raid,
the increasingly high losses and the fact that the Hyperbola (Gee)
navigation system could only be used in certain conditions, forced
the AOC-in-C of of Bomber Command to develop new systems of attack.
Using the German system of 'Illuminators' and 'Fire
Raisers' as a model, the use of Pathfinders was developed towards
the middle of August 1942, in order to bring on to the target all
the aircraft, some with inexperienced, others with only
medium-trained crews, and to allow the dropping of the bombs without
loss of time.
2. Air Vice-Marshall BENNET,
at present still in command of these special units, was appointed
Chief of the Pathfinder formations.
This 35 year old Australian - known as one of the
most resourceful officers of the RAF - had distinguished himself as
long ago as 1938 by a record long-range flight to South Africa in a
four- engined seaplane which was launched in the air from a
Sunderland flying boat (composite aircraft). In 1940 BENNET
established the Transatlantic Ferry Command with aircraft of the
Hudson type. As an example of his personal operational capabilities,
an attack may be cited which he made on the German Fleet base at
BENNET's appointment as Commander of the Pathfinder
Formations is also based on the fact that he has written two
standard books on astro-navigation.
3. The use of Pathfinders in
the first large-scale raids was comparatively primitive. Several
particularly experienced crews were sent out first as Fire Raisers
ahead of the Main Bomber Force and, in order to facilitate and
ensure the location of the target, moonlit nights were especially
Shortly after the formation of these Pathfinder
groups, however, the principle of raids during moonlit nights was
dropped and raids in dark cloudless periods began to take place.
BENNET strove to render the raids independent of the
weather and at the same time to make it easier for the less
experienced crews to locate the target.
4. At first there were only
four bomber squadrons, equipped with Stirlings, Halifaxes,
Lancasters and Wellingtons, and in January 1943 these units were
organised into No 8 Bomber Group, the Pathfinder Group.
The grouping of the Pathfinders into a Bomber Group
of their own made it possible to standardise the equipment and the
training, to put new ideas into operation and to immediately
evaluate all experiences.
During the course of 1943, the number of Pathfinder
squadrons was increased to meet the increased demands, and among
others, several Mosquito squadrons were detailed to the Pathfinder
B: ORGANISATION AND EQUIPMENT
I: Organisation and Aircraft Types
1. Eighth Bomber Group at
present consists: Five Lancaster squadrons, one Halifax squadron,
four Mosquito squadrons (including two special bomber squadrons with
'Bumerang' [Oboe] equipment) and one Mosquito Met Flight.
For further information concerning the organisation
of these units, see 'Blue Book Series', Book 1: The British Heavy
2. In addition to the normal
navigational aids (see also 'Blue Book Series', Book 7: British
Navigation Systems) the aircraft carry the following special
aircraft (Lancaster and Halifax):
Rotterdam (H2S) for location of target and bombing
without ground visibility;
Hyperbola navigation instrument (Gee);
Identification Friend-Foe (IFF); acoustic
night-fighter warning instrument 'Monica';
visual night-fighter warning instrument (Cathode ray
oscilloscope) 'Fish Pond'
provision for bomb-release in the cabin as well as
in the navigation room.
b) Twin-engined aircraft (Mosquito)
Hyperbola navigation instrument (Gee);
special equipment according to mission, for example
the existence of Mosquitos equipped with H2S have
not as yet been definitely established. According to latest
information, this special equipment does not yet seem to have been
installed in the Mosquito.
1. The crews are no longer
composed mainly of volunteers as was formerly the case. Owing to the
great demand and the heavy losses, crews are either posted to
Pathfinder units immediately after completing their training, or are
transferred from ordinary bomber squadrons. As in the past, however,
special promotion and the Golden Eagle badge are big inducements to
At first Pathfinder crews had to commit themselves
to 60 operational flights, but due to this high number there were
insufficient volunteers, and the figure was decreased to 45.
After transfer to a Pathfinder squadron, a certain
probationary period is undergone. The crews are not appointed
Pathfinders and awarded the Golden Eagle until they have proved
themselves capable of fulfilling the equipments by flying several
operations (about 14) over Germany. Before the award of the Golden
Eagle each member of the crew has to pass a special examination to
show that he is fully capable, of performing two functions on board,
for example gunner and mechanic, or mechanic and bomb-aimer, etc.
2. There is a special
Pathfinder school (NTU Upwood Special School). All new crews,
however, are sent on a special navigational course lasting 8-14 days
at a Navigation Training Unit, where particularly experienced
instructors, who have already completed their pathfinder tours,
train the crews in the operation of the special equipment and put
final polish on their already good navigational training.
New Pathfinder crews fly training flights over Great
Britain. These are usually made southwest from the Cambridge area,
course being set for the Isle of Man. On the return flight, a large
city, such as Birmingham or Manchester is approached, dummy bombing
using H2S is carried out, and target photographs are brought back to
the home base. Flights of this kind are flown to a strict time
schedule, just as in the case of a large-scale raid on Germany or
the Occupied Western Territories, and are taken into consideration
in the assessment of the crews as Pathfinders. If, on several
occasions the schedule is not adhered to, the crew is transferred to
an ordinary bomber squadron.
C: PATHFINDER OPERATIONS
The operational tactics of the Pathfinders have been
under constant development ever since the earliest days, and even
now cannot be considered as firmly established or completed. New
methods of target location and marking, as well as extensive
deceptive and diversionary measures against German defences are
evident in almost ever operation.
Whereas the attacks of the British heavy bombers
during the years 19421-43 lasted over an hour , the duration of the
attack has been progressively shortened so that today, a raid of
800-900 aircraft is compressed into 20 minutes at the most.
According to captured enemy information, the plan for the raid on
Berlin on 15/16 February 1944 called for about 900 aircraft in five
waves of 4 minutes each.
In spite of the increased danger of collision or of
dropping bombs on other aircraft which must be taken into account,
the aim has been achieved of allowing the German defences, the
Commands as well as the defence weapons themselves, only a fraction
of the time available to them during raids in the past.
The realisation of these aims was made possible by
the conscientious work of the Pathfinder group and by the high
training standard (especially regarding navigation) of the crews.
The markers over the approach and withdrawal courses
serve as navigational aids for all aircraft and above all they help
them to keep to the exact schedule of tines and positions along the
briefed course. Over the target, the markers of the Pathfinders
enable all aircraft to bomb accurately without loss of time.
Up to date, the following markers have been
a) Ground Markers:
also called cascade bombs, are red, green and yellow. Weather
conditions govern the setting of the barometric fuse, whereby the
Ground Marker container is detonated at a height varying from 800 to
5,000 metres, thereby releasing 60 flares which fall burning and
burn out of the ground.
Ground markers are mainly dropped in the target
area, but they are also sometimes used as Route Markers. Ground
Markers are also dropped in 10/10ths cloud in order to illuminate
the cloud base from below. When the clouds are thin, the crew can
see the glare without difficulty. The average duration of burning of
a Ground Marker is 3-4 minutes.
b) Sky Markers:
parachute flares, of which several are usually placed
simultaneously. As a rule, the flares used are red ones from which,
at regular intervals, quick-burning green flares ('dripping green
stars') drop out.
Besides these, green Sky Markers with red stars asn
, although comparatively seldon, green Sky Markers with yellow stars
are also used.
The bomb aimers are for the most part briefed to
drop their bombs into the middle of a group od Sky Markers. This
corrects the opinion held until now that two sky markers are set,
one to indicate the point of bomb release and the other to indicate
c) White and Yellowish
Flares: used chiefly to illuminate a target. They are also
sometimes used as dummy markers.
During raids in the autumn of 1943, the enemy
attempted to mark a target approach corridor by setting numerous
flares. It may be assumed that he dropped this system because of the
heavy losses inflicted by German single-engined fighters in the
a) As Track Markers:
or Indicators, Sky Markers are used in 10/10ths cloud.
b) Ground Markers:
(Spotfires) are red, green or yellow; red and yellow are mainly
used. A ground marker does not split up into different traces, but
burns with a single bright light for from 3-8 minutes.
NEW KINDS OF MARKERS (as yet not clearly
The enemy has often tried to introduce new kinds of
markers with varying lighting effects:
a) Among others, a
quick-falling flare bomb was observed lately. After it hit the
ground, 1 90 metre high column of sparks was observed, which slowly
descended in many colours. Confirmation, however, is not yet
b) To designate the
beginning and the end of the attack, a large reddish-yellow
'Fireball' has often been observed. Red flares fall from the
Fireball and at low heights these again split up into green stars.
The light intensity of these bombs is unusually high.
c) The so-called red
'Multi-Flashes' are apparently used as Route Markers,. They have
been observed sparkling to the ground at intervals of 2-3 seconds.
d) The enemy seem to have
stopped using enormous 1,800 kg size flare bombs. The reason for
this could not be determined.
III: Execution of Pathfinder
DIVIDING OF TH PATHFINDER CREWS
a) At present, Pathfinder
crews are divided into the following categories:Blind Markers, Blind
Backers-up, Visual Backers-up, Visual Markers, Supporters -
Pathfinder Main Force.
About 15% of the bombers used for a large-scale
operation are Pathfinders. For example, out of a strength of 900
aircraft, 120 would be Pathfinders, of which about 20 to 25 would be
Blind Markers, 30 to 45 would be Blind and Visual Backers-up and 60
to 70 would be Pathfinder Main Force.
b) Blind Markers:
It is the duty of the Blind Markers to locate the target using H2S
and to set Ground or Sky Markers, or both, according to weather
conditions, at zero hour minus 2 to 5 minutes.
The Blind Marker crew are responsible for the
success or the failure of the raid. They are more strictly bound to
the time schedule than all the other aircraft taking part in the
raid. They are not allowed to drop their markers if the schedule is
deviated from by more than one or two minutes, or if the instruments
fail, or fail to indicate accurately. In such cases the Blind Marker
aircraft automatically becomes part of the Pathfinder Main Force and
must drop its HE bomb load exactly at zero hour.
With smaller targets, it is the duty of the Blind
Markers to set flares over the target area, in order to illuminate
Another duty of good Blind Marker crews during the
initial stages of the attack is not only to set new markers, but
also to re-centre the attack. Experience has shown that the first
aircraft of the Main Force drop their bombs near the Markers but
that succeeding aircraft tend drop them short of the target area
during the progress of the attack. It is the duty of the Blind
Markers detailed for this purpose to bring the bombing back to the
original target by resetting the Markers past the first aiming point
in the direction of withdrawal.
For several months past, the Blind Markers have had
a further duty, In several operations it was repeatedly shown that
errors in the navigation of the Main Force occurred owing to
inaccurate wind forecasts. Experienced Pathfinders were therefore
instructed to transmit their established wind calculations to
England by W/T. Each Group picks up these reports and transmits them
every half-hour to the airborne bombers.
c) Blind Backers-Up:
The duties of the Blind Backers-up are similar to those of the
Blind Markers, except that they fly in the bomber stream. Thus, they
drop their Markers during the attack, also in accordance with a
strict previously laid down time schedule. Blind Backers-up are used
to set Ground Markers and, above all, Sky Markers, which are always
renewed by means of H2S and never visually.
d) Visual Backers-Up:
In order to give new Pathfinder crews a chance to gain experience
for future operations as Visual or Blind Markers, they are allowed
to set the new Markers visually; these, however are always of a
different colour. Theoretically, these Markers should be on, or very
near, to the original Markers, but as in practice this is very
seldom the case, the impression given is that of the target being
framed by markers. The bomb-aimers of the succeeding bombers are
therefore briefed to release their bombs in the centre of the
markers dropped by the Backers-up.
e) Visual Markers: An
attack on a small or pin-point target (definite industrial
installations, dockyards, etc) necessitates still more accurate
marking than is possible by the Blind Markers. The Visual Markers,
therefore, locate the target visually from medium height, sometimes
from as low as 1,500 metres, and then release their Ground Markers
on the centre of the target, in order to concentrate the attack of
the high-flying bombers. The Visual Markers are aided by the
illumination of the target area aided by several Blind Markers
f) Supporters: New
crews who come from training units or other squadrons and who are to
be trained as Pathfinders, fly their first operations in the
Pathfinder Main Force. They carry only mines or HE bombs, arrive
exactly at zero hour and try, at the first concentric bombing, to
create conditions necessary to allow the incendiary bombs of the
succeeding waves to take full effect.
Route Markers are set buy good Blind Marker crews
and are renewed during the approach of the Bomber Stream by further
good Blind Marker crews. Ground Markers (Spotfires) are sometimes
set visually, and sometimes by instruments, but Sky Markers used as
Track Markers or Indicators are set only by means of H2S.
The route of approach and withdrawal are generally
identified by three Markers set at especially prominent points or
turning points. The colours of these markers for any single night
raid are usually the same: either red, green, yellow or white. It
has often been observed that the Route Markers do not always lie
exactly on course. They are set somewhat to one side so that the
approaching bombers are not unnecessarily exposed to the danger of
The Target Markers will differ according to weather
conditions. More Sky or Ground Markers are set, according to the
visibility and cloud conditions prevailing. Up to date, the
following methods of attack and target marking have been recognised:
a) The 'Parramatta' attack
under a clear sky and with good visibilty. Ground Markers are used
b) The 'Wanganui' attack
with 8-10/10ths cloud cover. Sky Markers only.
c) The 'Musical Parramatta'
attack with 5-8/10ths cloud cover. Mainly Ground Markers, but some
d) The 'Newhaven'
attack, in which the target area is illuminated by means of
parachute flares, coupled with several Ground Markers.
e) The 'Musical Wanganui'
attack with 8-10/10ths cloud cover. Mainly Sky Markers, but some
Ground Markers. This system of target marking has been used to a
great extent lately during bad-weather operations.
DROPPING THE MARKERS
The setting of the Pathfinder Markers requires a
great deal of experience. For this reason, training flights with
Markers of all kinds are often carried out over Great Britain,
serving for practical experiments with flares as well as for
When the target area is already illuminated by
previously dropped flares, the Ground Markers are released visually
by means of the ordinary bomb-sight. In cases where 10/10ths cloud
or dark conditions are found over the target area, H2S is used for
dropping all Markers.
A great deal of experience is required for the
setting of Blind Markers. Close co-operation between the navigator
and the H2S operator (see 'Blue Book Series', Book 7: British
Navigations Systems for the difference between the two) who sit
side by side in the navigation room, is the first essential for the
precise setting of Markers by means of H2S. Above all, drift must be
calculated before the Markers are set, so that the Main attacking
force has only to navigate on the Markers themselves.
The basis for all Pathfinder navigation is dead
reckoning, and all other systems are only aids to check and
supplement this. H2S equipment is valueless without dead reckoning
because the ground is not shown on the cathode ray tube as it is on
To facilitate the location of the target, an
auxiliary target, which experience shows to give a clear picture on
the cathode ray tube, is given during briefing. This auxiliary
target should be as close to the actual as possible, in order to
eliminate all sources of error. Cities, large lakes, or sometimes
even coastline features are used as auxiliary targets.
The course and the time of flight from the auxiliary
target to the actual target are calculated in advance, taking the
wind into consideration. The H2S operator then knows that the main
target will appear on the screen a given number of seconds after the
auxiliary target has been identified.
MOSQUITO PATHFINDER OPERATIONS
The Mosquito aircraft have special duties as
Pathfinders, concerning which the following information is
a) Setting Ordinary
Markers: 15 to 20 minutes before the beginning of the actual
attack, in conjunction with other Lancaster Pathfinders, over an
b) Setting Dummy Markers:
along the coast and at other places to indicate a false course and a
c) Dropping so-called
'Fighter Flares': these are imitations of the white and yellow
flares dropped by German flare-carrying aircraft, to attract and
divert German night-fighters.
d) Dropping 'Window' from
great heights: this is so timed, after taking wind conditions
into consideration, that a cloud of Window will be over the target
when the first four-engined Pathfinders get there. This is made
necessary by the fact that the target must be approached in straight
and level flight, without evasive action, in order to get a good H2S
picture. It is supposed to eliminate to a great extent aimed (radar)
fire by the Flak.
e) Release of Single HE
Bombs: 20 to 30 minutes after the main attack and observation of
the results of the main attack.
f) Identification of
pin-point targets: for succeeding Mosquito waves by setting
Ground Markers with the aid of 'Bumerang' (Oboe). The succeeding
Mosquitos then drop their bombs visually on the marked target.
1. Strong criticism from
amongst their own units was at first levelled against the British
Pathfinder operations, but they were able to prevail because of the
successes achieved during the years 1943/44.
2. The original assumption
that the majority of bomber crews would be less careful in their
navigation once they became used to the help of the Pathfinders, and
that therefore the total efficiency and success of raids would
diminish, has hitherto not been confirmed. The navigational training
and equipment of the ordinary British bomber crews has also been
3. The operational tactics
of the Pathfinders cannot be considered as complete even today.
There are, in particular, continual changes of all markers and
4. The trend of development
will be towards making possible on one and the same night two or
more large raids on the present scale, each with the usual
Units of the Rdl an Obdl
Luftflotten down to operational Gruppen
Flakabteilungen an Ln Regiments
(Source: No 61008 Secret Ic/ Foreign Air Forces;