Navigation and Bombing System

Navigating at
50,000 and
500 feet in
the 1960s
Air Commodore Norman Bonnor
1961
Just after
joining XV
Squadron
I was 21!
V-Force Nav Radar
1961 – 63 XV Squadron, Victor B Mk 1A
Select Star Crew
RAF Cottesmore
1964 – 66 100 Squadron, Victor B Mk 2
Command Crew
and Bombing Leader
RAF Wittering
Victor B Mk 1A
XV Squadron flew Victors at
Cottesmore from
16 Sept 58 to 31 Oct 64
Navigation Equipment
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True Airspeed Unit
Green Satin Doppler Radar
Ground Position Indicator Mk 4
Navigation and Bombing System
H2S Mk 9A Ground Mapping Radar
Radar Altimeter
G4B Gyro Magnetic Compass
Periscopic Sextant
Instrument Landing System
GEE Mk 3 later replaced by TACAN
Green Satin Doppler Radar
and GPI Mk 4
Navigation Equipment
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•
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True Airspeed Unit
Green Satin Doppler Radar
Ground Position Indicator Mk 4
Navigation and Bombing System
H2S Mk 9A Ground Mapping Radar
Radar Altimeter
G4B Gyro Magnetic Compass
Periscopic Sextant
Instrument Landing System
GEE Mk 3 later replaced by TACAN
Navigation and Bombing
System
Not exactly a miniaturised system!
The NBS Nav Panel
Navigation Equipment
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True Airspeed Unit
Green Satin Doppler Radar
Ground Position Indicator Mk 4
Navigation and Bombing System
H2S Mk 9A Ground Mapping Radar
Radar Altimeter
G4B Gyro Magnetic Compass
Periscopic Sextant
Instrument Landing System
GEE Mk 3 later replaced by TACAN
Navigation and Bombing
System
Navigation Equipment
•
•
•
•
•
•
•
•
•
•
True Airspeed Unit
Green Satin Doppler Radar
Ground Position Indicator Mk 4
Navigation and Bombing System
H2S Mk 9A Ground Mapping Radar
Radar Altimeter
G4B Gyro Magnetic Compass
Periscopic Sextant
Instrument Landing System
GEE Mk 3 later replaced by TACAN
Periscopic Sextant
Using the Periscopic Sextant
Navigation Equipment
•
•
•
•
•
•
•
•
•
•
True Airspeed Unit
Green Satin Doppler Radar
Ground Position Indicator Mk 4
Navigation and Bombing System
H2S Mk 9A Ground Mapping Radar
Radar Altimeter
G4B Gyro Magnetic Compass
Periscopic Sextant
Instrument Landing System
GEE Mk 3 later replaced by TACAN
Navigation Techniques
• Primary – all systems available: with
fixes from the H2S mapping radar
• Secondary - H2S mapping radar not
available: astro and radio position lines
used for positioning
• Limited – neither H2S mapping radar nor
Doppler velocities or drift available: air
data used for velocities with astro and
radio position lines used for positioning
DR Navigation
on the Victor Mk 1
• Doppler Radar Drift and Groundspeed were very
accurate
• True Heading from the Gyro Magnetic Compass
was poor; why:
– Large dynamic errors
– Lack of accurate knowledge of Variation
• We reduced the errors by completing airborne
compass swings using the sextant in our normal
operating conditions (45,000ft and Mach 0·84)
• In-flight compass errors in each of the 8 aircraft
on XV Squadron were almost identical
• DR Navigation accuracy was much improved using
airborne compass swing deviations
Navigation Fixing
on the Victor Mk 1
• Ground mapping radar was designed for
bombing, so fixing accuracy was very good,
but transmissions were easily detectable by
AI fighters and homing missiles
• Use of Astro fixing gave autonomy and
radio silence
– Sandwich fixes favoured
– At least 5 one-minute sights averaged
(in effect 300 individual measurements)
– Corrections applied for turning and
longitudinal accelerations experienced
during the sights
Conventional Armament:
Large Bomb Bay
34 ft long, 9 ft wide, 7 ft deep
5 Septuple Carriers
5 x 7 x 1000lbs = 35,000lbs


35 x 1000 = 35,000 lbs
35 x 1000 lbs
Grapple Y Test
Nuclear Armament:
Yellow Sun Mk 1 & 2 – 7,000 lbs
3 ft
Yellow Sun 1 – Green Grass – 600 Kilotons
Yellow Sun 2 - Red Snow – 1·1 Megatons
Bombing Tactics
• High Level 45,000 feet and above
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–
–
–
–
Type 1 – visual
Type 2 – H2S radar (usually with long offsets)
Type 2A – H2S radar with evasion
Type 2B – H2S radar with jamming
Type 2C – H2S radar with evasion and jamming
Offset Bombing
Offset 1

N
Offset 2
∆
T
Aircraft
Track
Offset 3
Offsets were referenced to
True North and up to
20,000 yards N/S and E/W
Free Fall Bombing
• Initially I would use a beam offset so that any
compass errors were propagated in range only,
and the aircraft track to the release point for
the target was correct
• At the last minute, I told the pilot to stop the
autopilot following the H2S steering demand and
freeze on heading
• I then switched to an along track offset beyond
the target so that I could correct any range
errors
• Using this technique, I could regularly achieve
bombing accuracy of less that 250 yards from
45,000feet
• We dropped some 100lb practice bombs at
weapons ranges, but most bombing practice was
made against RBSUs
RBSUs
• Radar Bomb Scoring Units
• Anti-Aircraft Gun-laying Radars that tracked and
scored us against simulated targets (40 or more)
in each range area
• Five RBSUs in UK and others in USA
– Highfly covering Greater London at Hendon
– Brantub covering East Anglia at Methwold
– Glenrun covering Glasgow at Abbotsinch
– Rainbelt covering Newcastle at Ouston
– Rubycorn covering Manchester at Haydock
Soviet Surface-to-Air
Missiles and Jammers
SA-1 Guild
SA-2 Guideline
Radar Jammer
Bombing Tactics
• High Level 45,000 feet and above
–
–
–
–
–
Type 1 – visual
Type 2 – H2S radar (usually with long offsets)
Type 2A – H2S radar with evasion
Type 2B – H2S radar with jamming
Type 2C – H2S radar with evasion and jamming
RBSUs had tuneable jammers for Type 2B & C attacks
Soviet Surface-to-Air
Missiles
SA-1 Guild
SA-2 Guideline
SA-3 Goa
Navigation at 500ft
• GM Compass and Doppler Velocities still
the primary Dead Reckoning aid
• H2S Radar still the main fixing aid, but the
radar horizon and hill shading restricted
radar range
• Also height of an object became more
important than what it was made of
• The Nav Plotter gave a running commentary
of what the Pilots should be seeing
• The Pilots attempted to confirm the
commentary from visual sightings!
Low Level Bombing Tactics
• High Level 45,000 feet and above
–
–
–
–
–
Type 1 – visual
Type 2 – H2S radar (usually with long offsets)
Type 2A – H2S radar with evasion
Type 2B – H2S radar with jamming
Type 2C – H2S radar with evasion and jamming
• Low Level Pop Ups from 500 feet
– Type 2D – to 20,000 feet with Yellow Sun 2
– Type 2E – to 10,000 feet with Yellow Sun 2
– Type 2F – laydown – Vulcan with WE177
Victor B Mk 2
100 Squadron flew Victors at
Wittering from
1 May 62 to 30 Sept 68
Victor with Blue Steel
Blue Steel
Span - 13 ft; Length - 35 ft; Diameter - 4 ft;
Weight - 16,000 lbs; Rocket thrust 26,000 lbs
Warhead Red Snow – 1·1 Megatons
Same Physics package as Yellow Sun 2
Modifications for Blue Steel
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•
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Uprated RR Conway engines
Blue Steel Cooling Pack in bomb bay
Modified Bomb Doors
Blue Steel Control Panel in rear cockpit
Other Blue Steel mods such as data transfer
cabling and cooling pack
• Ground Position Indicator - GPI Mk 6
GPI Mk 6
Navigation with Blue Steel
• We had to assumed a Scramble take-off so could
NOT start and align Blue Steel Missile’s Inertial
Navigation System on the ground
• We started it in the climb and levelled the
platform by forcing Inertial velocities to equal
the Doppler Radar (Green Satin) velocities
• This Doppler/IN Velocity mixing continued
whenever the Doppler was locked-on
• Initially aligned IN Azimuth Gyro to compass
heading then used Fix Monitored Azimuth (FMA)
– An accurate Radar fix every 20 minutes
– Any cross-track error assumed to be IN
heading misalignment and Azimuth Gyro
precessed to correct the error
– Continued regular FMA until missile launch
Typical Training Flights
• High Level Profile
– 8 minutes to 45,000ft
– Then cruise climb to 55,000ft plus as weight
reduced
– 6 hours at high level including:
• 1,000 nm Navigation exercise
• 3 or 4 simulated bombing runs (5 RBSUs)
• Fighter affiliation in North Sea
• ECM jamming runs at Stornoway
– Descent into circuit work before landing
Blue Steel – High Level Launch
M3.0
6 Minutes
after release
150 nm
Release Point Fix
Typical Training Flights
• High-Low-High Profile
– 8 minutes to 45,000ft
• 1,000 nm High Level Navex
– Descent to Low Level:
• 500 nm Navex (250/350 knots at < 500 ft)
• Simulated bombing run:
YS2 pop up attack to 10,000 ft or
Blue Steel simulated launch and carry over
– High level recovery and descent into
circuit work before landing
Blue Steel – Low Level Launch
M 2.5
2 Minutes
after release
45 nm
The Nav Plotter’s Office
44
The Nav Radar’s Office
H2S Mk 9A Radar Screen
12 inches
Range
switch
H2S Mk 9A Radar Screen
36 inches
12 inches
+
1
½
¼
½
8
Scales
million = 240 miles
million = 120 miles
million = 60 miles
million = 30 miles
Navigation and Bombing
System
Typical PPI Display at
Low Level
Rapid Processing Unit (RPU)
• H2S Scanner locked sideways at 90
degrees to Track
• Video transferred to the RPU’s 6 inch,
low afterglow CRT
• Photographic paper drawn passed the
CRT at a speed proportional to
Groundspeed
• Paper developed and displayed for Nav
Radar to use for fixing
• System probably a trial for future use
in TSR2
The Humber and Goole
Goole
Scunthorpe
Scunthorpe
RPU vs PPI
Operation Fresno
27 May 1966
Victor XL190
With Blue Steel No. 175
Holyhead Groyne


Ullswater


Swansea Harbour


Low Level Launch
Missile released at 500 feet, 350 knots…
100 foot lanyard
Low Level Launch
… end of the lanyard started the engine…
100 foot lanyard
PING !
Low Level Launch
…the missile pitched-up and climbed!
Low Level Launch
….and tried to shoot us down!!!
Achieved 410 yards error
at the 7,500 ft airburst over the target
We came back without it!
Navigating at
50,000 and
500 feet in
the 1960s
Air Commodore Norman Bonnor