The Battle of Britain Adrian Stewart Copyrighted Presentation Mike Lavelle 2015 - The 75 th Anniversary Remembrance David Lednicer - 8 April 2015 Events

The Battle of BritainThe Battle of Britain

Adrian Stewart

Copyrighted Presentation Mike Lavelle

2015 - The 75th Anniversary Remembrance David Lednicer - 8 April 2015

Events that Influenced the Battle of Britain



The Real Story: British Fighters vs. German Fighters


• British fighters:– Hawker Hurricane I – Supermarine Spitfire I & II– Boulton Paul Defiant I

• German:– Messerschmitt Bf 109E– Messerschmitt BF 110C

The Opponents

The Battle of BritainThe Battle of Britain• Hawker

– Sidney Camm– Roy Chaplin

• Vickers Supermarine– R.J. Mitchell– Joseph Smith (after 1937)– Beverly Shenstone

• Boulton Paul– John Dudley North

• Messerschmitt (Bayerische Flugzeugwerke until 1938)– Willy Messerschmitt– Robert Lusser

Principal Designers


• Designed to Specification F.5/34– Interceptor monoplane with eight

machine guns and speeds in excess of 300 mph

– Specification F.36/34 written to match Hawker design submission

• Conservative design for 1935– Space-frame, fabric covered fuselage

and wings– Stressed-skin metal wing later

introduced– Unsophisticated aerodynamics

Hurricane Development

Fuel tanks


• Designed to Specification F.7/30

– Monoplane “zone” fighter with four machine guns and speeds in excess of 215 mph

– Specification F.10/35 written to match Supermarine design submission

• Advanced design for 1935

– Stressed-skin metal fuselage and wing

– Sophisticated aerodynamics

Spitfire Development

Fuel tanks


• Designed to Specification F.9/35

– Two-seat four-gun turret fighter

– “Bomber destroyer” concept

– No forward-firing armament



– Modestly sophisticated aerodynamics

Defiant Development

Fuel tanks


• Designed to specification L.A. 1432/33– Short-range interceptor with top speed

of 250 mph at 19,690 feet– Climb to 19,690 feet in 17 minutes

and flight duration of 90 minutes• Advanced design for 1934

– Power increased by 50% with installation of fuel-injected DB 601A in the Bf 109E

– Stressed-skin metal fuselage and wing– Sophisticated aerodynamics

Bf 109 Development

Fuel tank


• Designed against a RLM request

– Long-range twin-engine, three-seat, all-metal monoplane

– Armed with cannon



– Sophisticated aerodynamics

Bf 110 Development

Fuel tanks


• Hurricane fuel header tank was not isolated from the cockpit

• Spitfire fuel tank was ahead of the fireproof bulkhead

• Self-sealing capability and armor added to Hurricane and Spitfire fuel tanks during the Battle of Britain

• Bf 109E did not have a self-sealing fuel tank

• Bf 110C did have a self-sealing fuel tanks

Fire Danger

Flt Lt James Nicolson, only member of the

Fighter Command to be awarded a Victoria

Cross during the Battle of Britain


• Cockpits were not pressurized– Pilots breathing 100% oxygen above

15,000 feet• Cockpits reported to be well-heated • G-suits not invented yet• Flight suits were not fire-resistant

– Nomex fabric not invented yet• Over-water survival suits not invented yet• Crash helmets not invented yet• Rescue radios and beacons not invented yet

Flying Kit

The Battle of BritainThe Battle of BritainAerodynamics – Pressure Distributions

NACA 22XX airfoils

NACA 2R1 XX airfoils

Note forward loading on airfoils

Hurricane design used older Clark YH airfoil

The Battle of BritainThe Battle of BritainLater Designs, for Comparison

Airfoil loaded further aft


• Spitfire I & II

– Radiator on right, oil cooler on left

• Hurricane I & Defiant I

– Radiator on centerline

• Bf 109E & Bf 110C

– Radiators on both sides

Cooling System Ducts


• Rolls Royce Merlin II– 27 litre V-12– 1,030 hp at sea level– Single stage, single speed direct-

drive supercharger– 100 octane fuel

• Daimler Benz DB 601A– 34 litre inverted V-12– 1,085 hp at sea level– Single stage, single speed

hydraulic-drive supercharger– 87 octane fuel

Engines

The Battle of BritainThe Battle of BritainEngines

0

5000

10000

15000

20000

25000

30000

0 200 400 600 800 1000 1200 1400

Altit

ude

(fee

t)

Power Output (hp)

Merlin II 6.25 psi boost

Merlin III 12 psi boost

DB 601A 1.3 atm boost

DB 601A 1.4 atm boost

Supercharging maintains power to higher altitude

1.3 atm = 4.41 psi boost1.4 atm = 5.88 psi boost

Merlins could run at higher boost, partly due

to higher octane fuel


• Hurricane

– 600 miles

• Spitfire

– 395 miles

• Defiant

– 465 miles

• Bf 109E

– 410 miles

• Bf 110C

– 900 miles

Radius of Action

200 mile radius

100 mile radius


• Bf 110C

– 2 x 20 mm MG-FFM cannon in nose

– 4 x 7.92 mm MG 17 machine guns in nose

– 1 x 7.92 mm MG 17 machine gun aft-facing

• Hurricane and Spitfire

– 8 x 0.303 caliber machine guns

• Defiant

– 4 x 0.303 caliber machine guns in turret

• Bf 109E

– 2 x 7.92 mm MG 17 machine guns in cowling

– 2 x 20 mm MG-FF or FFM wing cannon

Armament

Cannon shells contain explosive,

bullets don’t

The Battle of BritainThe Battle of BritainVisibility• Hurricane I

– Framing obscures view

– Little rearward visibility

– Rear-view mirror

– Bullet resistant glass windshield• Spitfire I & II

– Good visibility in all directions

– Rear-view mirror

– Bullet resistant glass windshield

• Bf 109E

– Framing obscures view

– Very tight

– No rear-view mirror

– Some had bullet resistant glass windshields


• Early warning

– British had long-range aerial coverage with centralized command and control

– Germans only used radar to monitor shipping

• Combat formations

– Germans used “fluid four”

– British quickly adopted this

• Sun position

– Mornings favored Germans

– Afternoons favored British

Tactical Considerations


• Level speed

• Rate of climb

• Turning radius

• Roll rate

• Diving

• Ceiling

Maneuvering Factors

The Battle of BritainThe Battle of BritainCombat Pattern

Luftwaffe bombers at 16-20,000 feet

Luftwaffe escort fighters

Goal of RAF fighters

Altitude

The Battle of BritainThe Battle of BritainClimb Performance

0

5000

10000

15000

20000

25000

30000

35000

0 500 1000 1500 2000 2500 3000 3500 4000

Altit

ude

(fee

t)

Rate of Climb (feet/min)

Spitfire I 6.25 psi boost

Hurricane I 12 psi boost

Hurricane I 6.25 psi boost

Defiant I 6.25 psi boost

Bf 109E

Bf 110C

The Battle of BritainThe Battle of BritainLevel Speed

0

5000

10000

15000

20000

25000

30000

35000

0 50 100 150 200 250 300 350 400

Altit

ude

(fee

t)

Level Speed (mph true)

Spitfire I 6.25 psi boost

Spitfire I 12 psi boost

Hurricane I 6.25 psi boost

Hurricane I 12 psi boost

Defiant I 6.25 psi boost

BF 109E

Bf 109E 1.33 atm boost

Bf 110C-1

The Battle of BritainThe Battle of BritainTurn Radius

-1000

-800

-600

-400

-200

0

200

400

600

800

1000

-800 -400 0 400 800 1200 1600 2000 2400

feet

feet

Hurricane I

Spitfire I

Bf 109E

Bf 110C

14 second turn

The Battle of BritainThe Battle of BritainRoll Rate

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

0 50 100 150 200 250 300 350 400

Tim

e to

45

deg

of b

ank

(sec

)

Airspeed (mph IAS)

Sptifire I RAE

Sptifire V NACA

Hurricane I NACA

Bf 109E RAE

Fabric covered ailerons

Metal covered ailerons


0

50

100

150

200

250

300

350

400

450

500

Hurricane I Spitfire I Defiant I Bf 109E Bf 110C

Indi

cate

d Ai

rspe

ed (m

ph)

DivingControl problems made this speed

hazardous

The Battle of BritainThe Battle of BritainDive Initiation Issue

• RR Merlin had a SU carburetor – If a dive was started with a push-over, the fuel

flow would be disrupted by the negative gs– Engine would cut out– Dives had to be initiated with a half-roll, then a

pull– Problem fixed (in 1941) with a restrictor

diaphragm, developed by Beatrice 'Tilly' Shilling of the RAE

• DB 601A was fuel injected– Bosch had precision machining necessary to build

metering pumps– Dives could be started with a push-over

The Battle of BritainThe Battle of BritainAltitude Performance

0

5,000

10,000

15,000

20,000

25,000

30,000

35,000

40,000

Hurricane I Spitfire I Defiant I Bf 109E Bf 110C

Altit

ude

(fee

t)

The Battle of BritainThe Battle of BritainConclusion

• Defiant I– Ill-conceived concept– Poor performance– Withdrawn from day combat in late August 1940

• Bf 110C– Good firepower and range– Lacked maneuverability

• Spitfire I and Bf 109E– Closely matched– Bf 109E had insufficient fuel

• Hurricane I– Outclassed, but still useful

The Battle of BritainThe Battle of BritainThe Outcome

• RAF lost:– 1,547 aircraft– 544 aircrew

• Luftwaffe lost:– 1,887 aircraft– 2,698 aircrew

• Defenders decisively defeated potential invaders



Why All This is Important to Me

My Family’s Escape: May 10 to June 1940

Departed Lisbon for Brazil November 19, 1940

The Battle of BritainThe Battle of BritainWhere to See the Aircraft

• Spitfire

– Historic Flight Foundation (LF Mk.Ixe)

– Flying Heritage Collection (LF Mk.Vc)

• Hurricane

– Flying Heritage Collection (Sea Hurricane Mk XII)

• Defiant I

– RAF Museum in Hendon UK

• Bf 109E

– Flying Heritage Collection

• Bf 110C

– Several survivors in Europe

Documents

The Battle of Britain Adrian Stewart Copyrighted Presentation Mike Lavelle 2015 - The 75 th Anniversary Remembrance David Lednicer - 8 April 2015 Events