Warplanes of Germany: Luftwaffe Blohm + Voss BV 40

Blohm + Voss BV 40 glider interceptor

(Blohm & Voss Photo)

 Blohm & Voss BV 40, coded PN + IA. This was the first prototype, which was lost on its second test flight.

The Blohm & Voss BV 40 was a prototyp armoured German glider initiallydesigned in mid-1943 by Blohm& Voss to attack Allied bomber formationsduring . The BV 40 would be towed to highaltitude by single-engined fighters andthen ram the bombers while in a dive, but this concept was rejected before itsfirst flight in May 1944 in favour of using its guns. The Luftwaffe had lostinterest in the BV 40's original mission the month prior; development continuedas its mission changed to attacking ships with specialized bombs. Blohm &Voss discovered that the prototypes were significantly overweight, and some ofthe armour and one gun had to be removed to conduct flighttesting. The BV 40 was cancelled in August with only 6 gliders completedout of the 21 ordered. All of the aircraft were destroyed in an air raid inOctober.

Construction of sixprototypes began in December 1943, designated V1–V6 (German: Versuchs, 'Experimental'),including one airframe for stress testing to destruction, and another 15 prototypes were ordered on 15 February 1944. As production progressed,over-optimistic weight estimates were revealed during a meeting on 16 Februaryand a drastic weight reduction program had to be implemented. Blohm & Vossinformed the Air Ministry that the six gliders already begun would have to belightened by 182 kilograms (401 lb) to allow flight testing to begin asscheduled. The changes included the substitution of wood for steel in the uppercanopy and the sliding steel shutters, and ordinary glass for the bulletproof windscreen. One gun and its ammunition and armour would be deleted as would theleg armour.

At the same time, thespecifications for the production BV 40s were also modified to save 144.5kilograms (319 lb), bringing the gross weight down to approximately 1,000kilograms (2,200 lb). All 8-millimetre plates were reduced to 6 millimetres(0.24 in) in thickness, and the middle fuselage section was to use woodrather than sheet steel. In addition the ammunition armour was to bedeleted, lightening holes were to be drilled in moststructural members and the skin of the wings and flight control surfaces were reducedin thickness. These changes compromised the glider's structural strength, whichreduced its estimated safe diving speed to a maximum of 850 kilometres per hour(530 mph; 460 kn) above 4 kilometres (13,000 ft) and 700kilometres per hour (430 mph; 380 kn) closer to the ground. Rocketpropulsion was also considered, but was judged unsuitable.

The Office of theInspector of Fighters had lost interest in the BV 40 programme by 20 April, butdevelopment work continued under the auspices of Bomber Group 200 (Kampfgeschwader 200 (KG 200)), the Luftwaffe's specialoperations force. The unit had decided to investigate the possibility ofusing manned glide bombs against Allied invasion shipping. Blohm& Voss' response was to substitute a pair of BT700 (Bomben Torpedo) weapons for the gun pods, with the gliders tobe carried aloft by Heinkel He 177 heavybombers, one under each wing. TheBT700s were bombs that were designed to be dropped short of the target andtravel underwater before detonating. They had warheads thatweighed either 320 or 330 kilograms (710 or 730 lb).Whilenot strictly suicide weapons because the pilots couldpossibly pull up in time to avoid hitting their targets, the gliders would havenowhere to land and the armoured cockpits would sink very quickly.

The first prototypewas completed in late April 1944 and made an unsuccessful attempt to get offthe ground between 27 April and 2 May. A second attempt on 6 May wassuccessful, but the V1 was badly damaged while landing on 2 June. V2 had beencompleted by this time and took over the majority of the flight testingbeginning on 5 June that lasted until 26 July. The BV 40 made a total of 17 flights.Thehighest speed attained by any of the BV 40s was 470 kilometres per hour; 254knots (292 mph), and it was thought to have the potential to go farfaster.

Blohm & Vosslacked the resources to pursue the other variants of the BV 40 requested by KG200 and was not able to build any gliders beyond those already ordered. The AirMinistry had grown disenchanted with the programme by late July and acceded toa request by Blohm & Voss to stop further work on the incomplete aircrafton 27 July. By this time V7 of the second batch was on track to be completed inAugust and construction had begun on V8 through V14 with deliveries scheduledthrough March 1945. The Luftwaffe formally cancelled the programme on 13August. Blohm & Voss stored all of the BV 40s in a hangar at its airfield in Wenzendorf,but this was bombed by Consolidated B-24 Liberator heavy bombers on 6 Octoberand destroyed.  (Wikipedia)

(Blohm & Voss Photo)

 Blohm & Voss BV 40

(SDASM Photo)

 Blohm & Voss BV 40 Stummelhabicht, coded PN+UA, first prototype.

(Blohm + Voss Photo)

 Blohm & Voss BV 40 Stummelhabicht, coded PN+UA, first prototype.

(Blohm + Voss Photo)

Blohm & Voss BV 40 Stummelhabicht, coded PN+UA, first prototype.

(Blohm + Voss Photo)

Blohm & Voss BV 40 Stummelhabicht, coded PN+UA, first prototype.

 (Blohm + Voss Photo)

Blohm + Voss BV 40, glider interceptor (prototype).

 (Blohm + Voss Photo)

Blohm + Voss BV 40, glider interceptor.

(Nevington War Museum Photo)

Blohm + Voss BV 40, glider interceptor (prototype).

The BV 40 was a glider fighter designed to attack Allied bomber formations. By eliminating the engine and positioning the pilot in a prone position, the cross-sectional area of the aircraft made it harder for bomber gunners to hit it. The Bv 40 had a very narrow and heavily-armored cockpit, and two 30 mm (1.18 in) MK 108 cannons in the wing roots. For a time, the idea of carrying a bomb on a cable behind the glider was entertained.