| Condition: |
Engine BMW 801 D 2/25453
|
|
Tight engine cowling.
|
|
Split flaps with reinforced control linkage.
|
|
Armament: 2 MG 17, MG 2 151
|
|
MG-FF belt hatches
|
|
Armored ring mounting in accordance with BSK 190.6-941.
|
|
Rudder bell crank in accordance with KBZ 24326
|
|
(25 ° rudder deflection).
|
|
MG 151 fairing (without barrels) under the wings.
|
| Program: |
1. |
Change of flight characteristics due to the MG 151 fairing under the wings.
|
|
|
|
2. |
Loss of speed from the MG 151 fairing.
|
|
|
|
3. |
Assessment of the rudder forces with the bell cranks instead of differential 1: 1.8.
|
|
|
|
4. |
Climb and level
flights with a fuel tank pump at high altitudes (check of the BMW
proposal: fuel tank pump circuit coupled to fuel shut off valve).
|
|
|
|
5. |
Endurance testing of the armored ring mounting.
|
| Results: |
1. |
A significant degradation of the flying characteristics was not noticed with the addition of MG 151 pods under the wings.
From Va = 650 km/h there is only a slight, therefore unobjectionable, perturbation noticeable in the control stick.
|
|
|
|
2. |
The level speeds
obtained with combat power, with and without MG 151 fairing, are shown on
the attached graph. Both pods cause a loss of 26/29 km/h.
|
|
|
|
3. |
Instead of the rudder
differential, a bell crank was fitted for rudder deflections of 25°
and are in order with regard to forces at low speeds.
With increasing ram pressure the forces required even for small rudder
deflections are unacceptably large. More tests are currently running with bell cranks
for 20 ° rudder deflection.
|
|
|
|
4. |
To check the BMW
proposal, rear tank pump "on" at shut off valve position both or rear tank "on",
and front pump "on" at shut off valve
position front tank "on", climbs up to the ceiling as well as level
flights at high altitude were carried out, in addition to No. 665 also
with two other machines, with just one fuel tank pump (front or rear).
With Maihak-pump and tank pumps being in order,
the engine runs without any complaints up to ceiling, thereby
proving that the fuel supply, is also guaranteed with one fuel tank
pump.
From this point of view, there's no objection to switching the pump by means of fuel shut off valve.
|
|
|
|
5. |
No complaints have arisen so far with the armored ring mounting in accordance with BSK 941.
The total flight time of this construction is 13.5 hours.
|
|
|
Langenhagen, 20.5.1943
Gt/Kl.
|
|
