- A -
PROFILE - The
Air Ministry
was formerly a
department of the British government with the responsibility of
managing the affairs of the Royal Air Force. It existed
from 1.4.1914 to 1964. Different types of
aircraft compasses were built for the A.M.: the P Series compasses were
Pilot’s Compasses, the O Series being Observer's Compasses.
During WWII, they were built by several makers, not just Hughes. After
the serial number on the bezel, there is a suffix letter, which denotes
the manufacturer. Henry Hughes and Sons (later Kelvin Hughes) also made
compasses under the trade name Huson, the most common example being the
Huson Mk3.
We
display here just a few examples: The model 06A, a landing compass was
a
hand bearing
compass for use on the ground (for modern instruments see SESTREL,
SAURA).
Other compasses installed on-board of aircraft were based on a same
design like the P series. Some were equiped with a mirror and
the
O2 had an azimuth circle.
The compasses used by the RAF were aperiodic
compasses, i.e. they
settled onto a true course after a turn without overcompensation, this
being achieved by means of sophisticated features like strong magnetic
moment, small inertia and heavy damping. For further information
concerning navigation on RAF aircraft with
these compass types and more technical details concerning the aperiodic
compasses, please go to
cairdpublications.
The following information concerning the various P models' chronology
was sent by a friendly visitor. Any complementary data will be welcome:
Picture at
right courtesy
M. Goosey: A P12 compass (click on the image for an enlarged
view).
- The earliest that I have found in the P Series is the P3. This was a
vertical card compass dated about 1930. I suspect (but have no hard
evidence) that P1 and P2 were assigned to WW1 RFC (
Royal Flying
Corps, predecessor of the RAF) compasses that
remained in service after the Air Ministry was formed.
- The P4 was a mid-1930s compass and was used in
“large” aeroplanes, including the
Hawker Hart,
Sunderland
and early four-engined bombers. It was replaced by the P10, which was
identical in size but had four cross hairs rather than two. Some P4's
were modified with four cross hairs as P4A. It was the P10 that would
have been fitted to the
Lancaster
rather than the earlier P4, but I have no doubt that P4's were also
used
when the need arose.
-
I have no information about the P5.
- The P6 was fitted to “small” aeroplanes. It was
replaced by the P8, which had a slightly larger bezel.
- The P7 was an inverted version of the P6 and was replaced by the P9,
which was an inverted P8.
- The P8 was in common use from about 1937 and was used in the
Spitfire, Hurricane, Tiger Moth,
etc. and was replaced by the P11. There was also a version marked as
the P8M (M for MARINE ?). Some P8's
and P8M's were modified with four cross hairs.
- The P9 was an inverted version of the P8 and looked similar to the P7.
-
The P10 was an improved version of the P4 with four cross hairs.
- The P11 was an improved version of the P8 with four cross hairs.
-
The P12 was an inverted version of the P11 viewed via a mirror which
hung below the bezel
(see
picture). It probably was the last magnetic compass in the
P Series.
WARNING
- DANGEROUS
RADIATION
The
cardinals (N-E-S-W) and the
10-deg. markings on the compasses were made of a radioactive
compound (radium and zinc sulfide) which
is still very "hot" although the paint is no longer visible in
the dark. In 50 cm (1 1/2 ft) distance, the gamma radiation measured is
0.35 µSv/h (microsieverts/hour). The natural background
radiation is about 0.10 µSv/h. The
threshold for dangerous radiation is 0.30.
Click on picture for
an enlarged view
DON'T OPEN
THESE INSTRUMENTS AND NEVER MINGLE WITH RADIOACTIVE PARTS.
DON'T STAY DURING LONG PERIODS NEAR THEM.
PROFILE - Joachim Richter was a German watchmaker located Am
Wald 2, Ende Erzbergerstr. 75 Karlsruhe
31. Miscellaneous aeronautical equipment.
Automatic watch
Model
08/15 Military (pic.
Maistero/Watch Lounge).
He also built at least until 1945
pilots'
goggles (pic.
profifilm.de,
mod. 1935).
|
Model FK.16
(Führerkompass = pilot compass)
Pictures Henri Note
(Click for enlarged views) |
|
Technical
Data
- Weight: 206 gr
- Depth: 60 mm
- Diam 57 mm
The FK16 is a LUDOLPH development and product. It is also integrated in
their navigation equipment for divers.
|
- B -
PROFILE - Carl Bamberg was a German compass manufacturer located in
Friedenau
near Berlin.
For more information click
HERE.
See also Pocket Compasses
Pictures courtesy Horst
Kahnt
(click for enlarged views). |
|
Technical Data
- Diameter: 115 mm
- Height: 84 mm
- Weight: ... g ?
This compass has been installed in following vehicles: (?) |
PROFILE - PIONEER Instrument Company was created in 1919. It was
acquired by and became a Division of BENDIX Aviation Corporation,
New Jersey
(N.Y.) in 1928.
For more information go to WIkipedia.
The upper plate masks a lamp.
Pictures courtesy Tony
KING
(Click for enlarged view) |
Rear face (connectors) |
AIRCRAFT COMPASS
MARK VIII - TYPE 1822
Technical Data
- Broadth: 87 mm
- Height: 80 mm
- Weight: 883 g
Markings: BU. AERO. U.S. NAVY
F.S.S.C. No. : 33-C-800
MFR'S Part No.: 1822-1-B |
 |
Cut-away view (Installation instr.)
|
PIONEER
VEHICLE COMPASS - TYPE 1829
This compass was used in all sorts of land vehicles
incl. tanks. It is said to have also been used in aircraft
(Installation instr. avlbl.) but we lack evidence.
Pictures courtesy priv. coll.
(Click on images for enlarged views) |
The flight instrument below is a radio
compass
indicator. It is not a compass per se but an
indicator that has a needle coupled
to a synchro motor that is coupled (via a 5-wire cable, connector PL
118)
to another device or
mechanism that actually performs the compass function (e.g. flux
valve). The knob labeled VAR allows the calibrated
direction ring to be set (E-W) for variances in magnetic declination
that is
different at all localities over the world and varies over time
(especially as the airplane proceeds in an East-West direction).
Magnetic variation is noted on maps and aeronautical charts which
allows the pilot or navigator to correct
for this variation as the airplane proceeds from one location to
another.
(This definition was kindly given by LLoyd Crawford.)
(Click on the pictures for
enlarged views) |
 |
Radio compass /
Signal indicator I-82-A
Signal Corps U. S. Army
S/N: 4771
Period: WW2
Technical Data
- Diameter: 13 cm
- Depth: 9 cm
- Weight: 600 gr |
- C -
PROFILE - ...
The Online Compass Museum doesn't possess any information
about this
company. Your help is welcome. This company is kindly invited to
contact the curator.
PROFILE - Captain Frank Osborne Creagh-Osborne (1867/1943) was
Superintendent of Compasses at the
Admiralty
and a British inventor.
He developed several compass systems which were manufactured by H.
Hughes & Son Ltd, Dent & Co & Johnson Ltd and
also by Sperry Gyroscopes (see
also the sections Marching Compasses and Wrist Compasses). In 1915,
Henry
A. Hughes
took part in a meeting at the Admiralty and explained
the advantages of this compass (source: minutes of meeting in '
Improvements
in prismatic compasses with
special reference to the Creagh-Osborne patent compass' -
Ask for a copy).
Creagh-Osborne published in 1916 a booklet (
photocopies of the French
version available, 52 pages) about the use of compasses in
aircraft. He described therein not only the systems integrated in the
instrument panel but also the compasses utilised by the observer, i.e.
attached to his wrist by a leather strap.
According to Ellis Island's immigration records, he landed in
New
York on June 8, 1918 on board a ship called
Olympic
arriving from Southampton.
See also Marching and Wrist compasses
Description
and user instructions for Air Compasses (French edition)
(Click on the pictures for
enlarged views) |
Instrument
panel
compasses
Pattern 255 and 259
Observer's
wrist compass Pattern 261
 |
The
patent numbers indicated on the compasses (1148/15 and
17736/15) refer to the application documents and the year 1915 (copies available).
The compass type described in Pat. no. 17,736 is for the patterns
family 255/259. The numbering started in 1913 with 200 and the
compasses were issued from 1915 on.
Patent no. 1148 describes several prismatic and liquid dampened compass
types displayed in the
Marching
and the Wrist compasses sections. |
|
Air Compass Pattern
259
|
Technical
Data
- Dimensions (height x breadth): 152 x 135 mm
- Depth (w. lugs): 108 mm
- Depth (w/o lugs): 89 mm
- Weight: c.1.7 lb.
- Divisions: 360 deg. every 10.
- Fluid damping
|
Side view with the manufacturer's
label of HUGHES & SON Ltd. |
Air Compass
Type 5/17
Pictures
courtesy mfc80 |
Technical
Data
- Dimensions: ... x ... x ... mm
- Weight: lb.
- Divisions: 360 deg. every 10.
- Dry capsule
This extremely simplified compass was used in the famous WW1 Sopwith RFC/RAF
aircraft. The figure 5/17 means design-appproved
May 1917. More than 50,000 pcs were built. (Source: Steady as she goes,
Fanning, 1986).
|
- D -
PROFILE - Gaston-Jules DALOZ (living in Ramerupt,
Aube,
France) filed in Aug. 1910
a patent (no. 419.682) for a system that permitted to follow
the
displacement of the landscape on ground through the transparent card of
a compass (see detailed
description
and comment as published in
FLIGHT
no. 107, iss. Jan. 14, 1911). The parallel lines were introduced via an
additional patent in Nov. 1910.
The device was then further developed by Abel-Louis DOIGNON*
(patent no. 431.275, May 1911) who added a liquid damping and
mechanical solutions permitting a rapid (re-)setting.
In spite of this, the compass was not to be used as such (no cardinals)
and the pilot needed an additional standby-compass.
* See Doignon's marching compass.
The original Daloz-Patent
(Cover 9 2/4" x 1 ft) |
Original drawing of DALOZ's system
|
The further development
(DOIGNON's patent)
|
PROFILE - Deperdussin was a French aircraft manufacturer (see
Wikipedia) located 19, rue
des Entrepreneurs, Paris.
This instrument with a very unusual design was invented in
1912 by Gaston Emile Colombel who lived 50, rue de
Moscou, Paris (pat. no. 26,282, British issue). It was
installed in the following aircraft during the first crossings
of the Channel, three of them in thick
fog: Biélovucie flying a
Hanriot machine, Moineau
flying a
Bréguet,
Prévost a
Deperdussin,
Guillaux a
Clément).
The brochure & catalogue (13 p.,
fotocopy available on request)
also contains exerpts of letters sent by pilots after winning races:
- Crossing of the Alpes by Biélovucie in 1913.
- Coupe Pommery (1,129 km) won by Guillaux in April
1913.
- Races Paris-Amiens-Paris and
Circuit
Forézien
(400 km) won by Molla. The latter flew the best time on the
1st leg of the waterplane race from St. Malo to Jersey and
return in thick fog
(
letter dated Feb.1913).
A. Védrines thanked the inventor Colombel in the name of
Serbian Air Force pilots.
Model MONODEP 1912
Dampening of vibrations by means of springs.
|
Model MONODEP 1914
Gimballed item, scale with MILS divisions
(1/4 of full circle = 1600)
Pictures by courtesy of M. Collignon
(Click
on images for enlargement) |
Technical Data - (Functional
description / patent's fig.)*
The compass magnets are concealed in the bowl. The visible card rotates
in a vertical
plane and is linked to the magnets via a right-angle gear. Only the
cardinals are
painted on the card (red star for North).
The route to be flown is set on the external scale (graduated
90° or 1600 MILS for a full circle) by means of an
arm linked through the cover glass via a 1:4
gear to a second arm terminated by a red star which indicates the
position of the card's north red star. A full circle of the scale
corresponds thus with only a 1/4 of the card's rotation. The heading
measured on a map is set via a special protractor and the external arm
on the scale. The pilot only has to make sure that the two red
stars remain superimposed.
Model 1914 featured an integrated lighting with a battery which
could be replaced in flight (6 hrs life time). The card was
divided into four quarters of different colours and called Capitaine
ROISIN after its designer.
The magnetic declination could be set during production.! This seems
surprising now but in those days, the aircraft range was not big enough
to make an in-flight adjustment necessary.
* The patent describes a flat instrument. |
- H -
PROFILE - This manufacturer is not associated with
Hamilton Standard, a
U.S. Company created in the 1920's by Thomas Foster Hamilton (July 28,
1894
– August 12, 1969) who was a pioneering aviator and the
founder
of this company.
We received the following information:
'The Hamilton HI-400
Vertical Card Compass was invented by a man known
as "Ham" Hamilton at
Hobby Airport in Houston Texas in the early 1970s. He owned a small
aircraft instrument repair shop known as Hamilton Instruments at Hobby
Airport. I knew "Ham" at the time because I was an avionics technician
working for Associated Radio Service Company, also at Hobby Airport.
"Ham" brought his prototype into our shop and showed it to us. It was a
great invention. The model number "HI-400" stands for Hamilton
Instruments-400.
Hamilton later sold his
invention to Precision Airmotive, also at Hobby
Airport. These compasses are still being made, but it is momentarily
not known by whom. It is supposed that "Ham" is either very old now, or
has passed on.'
(Click on the picture for
enlarged view) |
 |
Technical
Data
- Dimensions: 70 x 60 x 50 mm
- Weight: 270 gr/0.6 lbs.
The deviation
can be compensated in order to show a correct display by turning the
screws at the lower front part:
the left-hand screw (green paint mark, upper one on pic. below) is for
the North-South axis and the one on the right
(painted yellow) is for the East-West axis.
 |
- K -
PROFILE - KEARFOTT is a North American manufacturer of flight
instruments (more information
HERE).
The instrument presented here is an evolution
of Kearfott's N-1
navigation system described in the diagramm below and which was
developed approximately in 1948. This large and
heavy
instrument comprises the gyroscope.
It is a highly accurate system that enables precise navigation on long
range flights by taking into account both the Earth's rotation and
curvature. This feature made it thus possible to perform grid
navigation, i.e. to fly directly on 'great circle' routes
and achieve the shortest possible distance between
two
points on the Earth.
Kearfott ultimately produced
around ten thousand systems for USAF and commercial applications. There
are still approximately 500 systems installed and active (e.g. in C-130
Hercules aircraft)
within the USAF inventory and the AF has an ongoing repair depot
activity (
complete
description in the original KEARFOTT document available).
Two pointers show the actual aircraft's heading and its position
between the Equator and one of the poles (LATITUDE: North hemisphere is
left, South is right).
(Source: ASTRONAUTICS Corp. of America)
Readings:
- Heading: 32°
- Position: 38° North
Knob top reads:
LATITUDE CORRECTION N-S
Knob bottom reads:
SYNCHRONIZER
(Click
for enlarged view)
|
Rear face: the connector and the related pin diagramm |
(Click to enlarge)
Functional
drawing of the basic N-1
system
The heavy instrument displayed here comprises both the indicator and
the gyroscope.
|
Technical
Data
- Dimensions:
120 x 120 x 220 mm
- Weight: approx. 4.5 kg / 9 lbs.
(Click
to enlarge)
|
Description:
Normally the small pointer on the latitude scale is set to "off" for
magnetic slaved operation. When running in "free gyro", then
the
small pointer is adjusted to the approximate latitude that the aircraft
is operating in and corrects the gyro for "earth rate" precession
('Free Gyro' operation is the normal operating mode in the arctic and
antarctic regions near the Earth's magnetic poles).
The latitude pointer is set by the navigator and it does not give any
position. Many times navigators operating in the antarctic
(particularly in the Southern Latitudes) have set their latitude as N
instead of S and suffered large induced corrections because of the
wrong latitude.
The very small pointer on the L / R indicator, indicates input by the
magnetic flux gate detector which is remoted on the wing or
other
portion of the fuselage. It will continuously fluctuate back and forth
as it receives the magnetic information.
(Explanations transmitted by Breckinridge S. Smith - Major, USAF ret.)
- L -
PROFILE - The French company Société des
établissements HENRY-LEPAUTE (11, rue
Desnouettes, Paris XVe) was a famous manufacturer
of clocks
and watches. It produced also numerous electrical and optical
materiels.
This compass type was patented in 1910 (no. 407.416).
Its
characteristical feature is the double pivot. The upper one's length
can be adjusted vertically (see image from Patent below).
PROFILE - W. LUDOLPH GmbH & Co. KG (Bremerhaven) is a German
company manufacturing nautical and aeronautical compasses.
(more information
HERE.
Examples of older compasses: FK 6, FK 10, FK 13
(FK = Führerkompass = pilot compass)
 |
(Pictures
courtesy www.spitfirespares.com) |
Model FK 10/32
Technical Data
- Compass of the Junkers 52
|
- N -
Dies ist ein sehr weites Feld und wir möchten hier nur einige
Aspekte kurz erwähnen.
So wie auf hoher See ist beim Fliegen der Kompass nur eines
der Instrumente, die die Navigation ermöglichen. Zwar konnten
frühere Flugzeugnavigatoren wie ein
Schiffskapitän ihre Lage (geographische
Länge und Breite) mithilfe eines hochgenauen Chronometers
und durch Beobachtung der Himmelsgestirne ermitteln.
Langstrecken-Flugzeuge waren mit Geräten ausgestattet, die
einen Blick auf
die Gestirne durch eine Öffnung an der Oberseite der
Flugzeugzelle ermöglichten. Wegen der
ungleich höheren Geschwindigkeiten jedoch mussten die
Berechnungen in viel kürzerer Zeit
als auf See erfolgen. Bevor moderne elektronische
Navigationsrechner diese
Aufgaben
übernahmen (vom
GPS
soll hier gar keine Rede sein), verwendete man hierzu
unterschiedliche Hilfsmittel.
Für Überlandflüge dienen
künstliche, am Boden installierte Referenzsysteme der
Orientierung
(Funkbaken, VOR -
siehe
Wikipedia). Es handelt sich um
Funksender, deren Signale mittels
Funkkompasse ausgewertet
werden (Beispiele:
Bendix
(USA),
UGR-4
(Sowjet-Union).
Wegen der raschen Veränderung der relativen Lage des
Magnetfeldes
durch die eigene Bewegung und um die Beeinflussung des
Anzeigegerätes
durch die mitgeführten Metallmassen wie Triebwerk, Bewaffnung
usw. zu
umgehen, wird das Erdmagnetfeld mittels einer
Magnetfeldsonde
(
flux valve or gate)
gemessen und an einen
Kurs-Kreiselkompass
weitergeleitet
(Beispiele:
Siemens-Halske,
Kearfott). Für den Fall,
dass diese elektrotechnischen bzw. elektronischen Hilfsmittel
ausfallen, verfügt jedes Luftfahrzeug
außerdem über
einen konventionellen
Notkompass, dessen Genauigkeit
jedoch äußerst niedrig ist.
Seitenwinde können ein Flugzeug vom Kurs
abbringen. Beispiele von Instrumenten zur
Berechnung der
Drift in Abhängigkeit von Windstärke und
-geschwindigkeit:
Dreiecksrechner
DR3 Tp (Wehrmacht 1943), Gerät xxxx im "
Knieplanchet"
NPL und yyyyyy (Kreissektorförmig, UdSSR),
Rechenschieber (NVA/DDR).
(Wenn nicht
anders angegeben, alle Fotos von K. Pätzold - Zum
Vergrößern, Bilder anklicken)
Dreiecksrechner Model DR-3
Tp, Wehrmacht
(1943)
Hersteller: Dennert & Pape. Ein anderes Modell war das
von K.
E. Tröger (Foto M. Dick)
|
Dreiecksrechner Model NPL
(UdSSR) im Oberschenkeltablett (Knieplanchet)
integriert
|
Driftberechnungsgerät
(Rote Armee / UdSSR)
mit Bedienungsanleitung
|
Rechenschieber
zur
Driftberechnung
(NVA / DDR) und Bedienungsanleitung
|
- P -
PIONEER
(no data available)
- R -
Radiation hazard, radioactivity
The self luminescent paint used for markings between the years 1915 and
1950 contained Radium. Click
HERE for more details.
See:
BENDIX (USA),
UGR-4 (Soviet-Union),
- S -
(Click on picture for
enlarged view) |
Stand-by compass (manufacturer
unknown)
The declination can be taken into account to show a correct display by
turning the screws concealed behind the plate at the lower front part:
- the left hand screw is for the north-south axis
and
- the right one for the east-west axis.
Technical Data
- Dimensions: 70 x 60 x 60 mm.
- Weight: 240 gr
- Date stamp: APR 82. |
PROFILE - Siemens Halske was the name of a German company established
in 1847 by Werner von Siemens and Johann Georg Halske called
Telegraphen-Bauanstalt von Siemens & Halske an located in
Berlin. (...)
...
The Online Compass Museum doesn't possess any further information about
this Company. Your help is welcome. This company (or its successor) is
kindly invited to contact the museum's curator.
Gyro-magnetic compass (Kurskreisel) Lku4, Siemens-Halske, built
1943-1945. This equipment was installed in the instrument panel of the
German Junkers aircraft Ju 52 and Ju 88.
The center picture shows a JU 88 cockpit. The Lku4 appears (in red) at
the top in the middle of the instrument panel.
Excerpt from the original notice "D.(Luft)T.5404", issued January 1943:
"The upper scale is the course setting rose. The desired course is set
by means of a motor activated by a flux valve. The lower scale shows
the actual course indicated by the inertial navigation system (gyro)."
Technical Data
- Dimensions: 160 x 130 x 120mm
- Weight: 2.6 kg.
(Click on picture for
detailled view of front and rear side) |
Flight deck and instrument panel of the Junkers Ju 88. The
Lku (in red) was located at the top, center.
(Click on picture for
an enlarged view) |
Technical Data
(original in German
dated March 1940)
|
PROFILE - SPERRY GYROSCOPE.
- U -
PROFILE - Russian radio compass.
Pictures
courtesy
K. Pätzold
|
Label YGR-4 Yk Seria 3
(Click for enlarged view)
|
Technical Data
- Diameter: mm
- Weight : kg
- Inscription on face: KURS - RP (?)
|
- V -
PROFILE - Former French company (for more information click
HERE)
Aircraft compass - model name and date unknown
Click
on pictures for enlarged views. |
|
Technical Data
- Diameter: 105mm
- Height: 60mm
- Gimbal structure:155mm wide (screw heads ), 100mm high.
- Weight: 2 pounds, 12 ounces
- Markings: VION PARIS et AÉRONAUTIQUE MILITAIRE
|
Aircraft compass patent (1928)
Click on the drawing above to enlarge the simple view or in the center
column for detailed original
patent illustrations. |
Patent - Figures (pdf files)
Figure 1
Figure 2
Figure 4
Figures 3 & 6
|
VION MANUALS
(photocopies available)
 |
Compass
type T.31
Pictures: VION Manual
(Click for
enlarged view) |
Compass type V.31
|
Technical
Data
The compass parts
 |
Compass type
Q.S.C.V. 29
(Click for
enlarged views) |
Compass type
G.N.R.V*. 30
(* Grande Navigation Rose Verticale)
|
Technical
Data
(see cell above)
Photocopies
availabe |
Compass
type F 37 B
(Click on the
picture for an enlarged view) |
Side view
 |
Technical
Data
Marking: Aéronautique militaire
(Pictures
courtesy MOGLIA - priv. coll.) |
Compass type QSC
27
|
|
Technical
Data
Compensation magnets
(Photo Houcke -
priv. coll.) |
Compass type PBA
60
Click on the picture for a view of the front face without the cover
plate |
Side view
Pictures courtesy
bieber231 - priv. coll. |
Technical
Data
Divisions: ... |
Compass
type H.A. 83
 |
...
|
Technical
Data
This model existed also in a 82 mm diam. version
(Pictures Jaypee -
priv- coll.) |
- X -
The following pictures show compasses with no manufacturer's name.
Pictures
courtesy A. Picker |
|
Picture at
right courtesy
M. Goosey: A P12 compass (click on the image for an enlarged
view).
-
The P10 was an improved version of the P4 with four cross hairs.
