| Fl. Nr.: |
Date: |
Take-off: |
Landing: |
Duration: |
Pilot:
|
| 13 |
4.9. |
14.55 |
15.08 |
8' |
Mehlhorn |
| 14 |
6.9. |
11.53 |
12.14 |
21' |
Finke |
| 15 |
6.9. |
15.35 |
16.24 |
49' |
Finke |
| 16 |
7.9. |
15.02 |
15.55 |
53' |
Finke |
| 17 |
7.9. |
17.32 |
18.13 |
41' |
Finke |
| 18 |
8.9. |
16.51 |
17.08 |
17' |
Finke |
| 19 |
9.9. |
12.10 |
12.36 |
26' |
Finke |
| 20 |
9.9. |
16.55 |
17.50 |
55' |
Finke |
| 21 |
10.9. |
9.00 |
9.48 |
48' |
Finke |
| 22 |
10.9. |
17.14 |
17.48 |
34' |
Finke |
| 23 |
13.9. |
11.07 |
11.48 |
41' |
Finke |
| 24 |
13.9. |
16.04 |
16.47 |
43' |
Finke |
| 25 |
13.9. |
17.14 |
17.37 |
23' |
Finke |
| 26 |
14.9. |
9.20 |
9.58 |
38' |
Märschel |
| 27 |
14.9. |
16.30 |
16.54 |
24' |
Bartsch |
| 28 |
15.9. |
8.48 |
9.17 |
29' |
Finke |
| 29 |
15.9. |
10.35 |
11.39 |
64' |
Sander |
| 30 |
15.9. |
16.44 |
16.54 |
10' |
Tank |
| 31 |
16.9. |
11.09 |
12.04 |
55' |
Finke |
| 32 |
20.9. |
14.28 |
14.57 |
29' |
Finke |
| 33 |
21.9. |
17.05 |
17.40 |
35' |
Finke |
| 34 |
29.9. |
15.15 |
15.18 |
3' |
Finke |
| 35 |
29.9. |
15.30 |
15.35 |
5' |
Finke |
| 36 |
23.10. |
10.52 |
11.28 |
36' |
Märschel |
| 37 |
23.10. |
15.14 |
16.00 |
46' |
Märschel |
| 38 |
24.10. |
16.25 |
16.55 |
30' |
Sander |
| 39 |
24.10. |
17.04 |
17.15 |
11' |
Sander |
| 40 |
27.10. |
16.16 |
16.33 |
17' |
Finke |
| 41 |
28.10. |
16.23 |
17.02 |
39' |
Finke |
| 42 |
31.10. |
14.34 |
15.00 |
26' |
Tank |
| 43 |
4.11. |
14.41 |
15.35 |
54' |
Finke |
| 44 |
4.11. |
16.06 |
16.53 |
47' |
Finke |
| 45 |
5.11. |
15.35 |
15.55 |
20' |
Finke |
| 46 |
6.11. |
14.05 |
14.55 |
50' |
Finke |
| 47 |
6.11. |
15.23 |
16.04 |
41' |
Finke |
| Condition: |
| Take off weight: G = 7,874 lbs (3575 kg); s = 0,628 m. |
| Engine BMW 801 F, V 85, with supercharger and Kommandogerät of the D-engine. |
| Tight engine cowling |
| Engine split flaps. |
| Single exhaust stacks. |
| Variable fan (9.8. to 7.9. not working properly, stuck at small pitch limiter). |
| Production fan with narrow blades V039 (from 8.9.43 on). |
| Replacement-nose armor (cooling gap 12-14 mm). |
| Oil cooler F 20750, W.Br.2080 - 1 (120/85 low with tube 5 on 6). |
| Thermostat Rö 17 or 19, set up to 40 - 60 °C. |
| Serial oil cooler venting, equal to D-engine with or without engine- and tank pendulum valve. |
| Blow off cock for supercharged air in case of boost fluctuation. |
| No armament, gun ports sealed. |
| ETC 501 under the fuselage (until 1.9.). |
| Fixed wheel doors. |
| Oil tank of F-engine 4215 B 1 from 25.9. on. |
| Internal intakes (until 24.9.). |
| External intakes from Paris production (from 25.9. on). |
| Production (rejected and repaired) tail wheel (from 16.9. on). |
| Program: |
| 1. | Ram pressure calibration on the test course. |
| 2. | Recording of the correlation curve in level flight at 500 m altitude. |
| 3. | Level speeds over altitude with combat and take off power. |
| a) | Internal intakes and variable fan |
| b) | Internal intakes with production fan with narrow blades. |
| c) | External intakes with production fan with narrow blades. |
| 4. | Climb rates at combat power with production fan. |
| a) | Internal intakes. |
| b) | External intakes. |
| 5. | Oil and cylinder temperatures in climb flight with combat power. |
| a) | Production fan. |
| b) | Variable fan. |
| 6. | Cooling pressure drop and pressure in front of the engine in climbing flight with combat power. |
| a) | External intakes and production fan |
| b) | Internal intakes and production fan. |
| c) | Internal intakes and variable fan. |
| 7. | Cooling pressure drop and pressure in front of the engine in level flight with take off and combat power in the condition internal intakes with production fan. |
| 8. | Cylinder temperatures of all cylinders in level flight with combat power. |
| 9. | General observations and faults. |
| Results: |
| 1) |
For the first time the chart 1 contains the ram pressure calibration as determined on the test course taking compressibility into account. In the future all speed figures
determined with BMW 801 F and Jumo 213 engines will be published with compressibility considered. For the aircraft with 801 D engines it will be continued to not apply
this conversion, to make comparisons with previously recorded values easier.
|
| 2) |
The correlation curve as determined near sea level for a check of the boost - rpm relation (chart 2) shows a boost equal to the nominal values for the rich part
and within the allowed tolerances for the lean part. The rich-lean switching point has been increased by 100 rpm from the 801 D engine and
is in between 2200 - 2300 rpm. |
| 3.a) |
The level speeds with combat power (n = 2500 rpm, Pl = 1.45) in condition 3 a of the program have not been depicted graphically. The adjustment forces of the
aneroid are presumed to be too small to adjust the blades towards higher pitch due to high mass forces. The screening of the pressure in front of the cylinder
block (see chart 10) caused by this results in a significantly reduced full throttle altitude (~ 1000 m) as well as a significantly reduced
level speed above full throttle altitude. |
| 3.b) |
As a temporary replacement the production fan of the D-engine (V039) was installed and with it the speeds over altitude with combat and take off power (n = 2700 rpm, Pl
= 1.65 ata), presented in chart 3 determined. From that chart the following, particularly interesting points, have been taken:
Combat power: H = 0 m, Vwck = 351 mph (564 km/h)
Full throttle altitude = 6550 m, Vwck = 423 mph (680 km/h)
Take off power: H = 0 m, Vwck = 365 mph (588 km/h)
Full throttle altitude = 6100 m, Vwck = 433 mph (696 km/h) . |
| 3.c) |
With the installation of the external intakes from serial production no level speed gain above full throttle altitude was obtained. As can be seen from the plot in chart
4, the full throttle altitude at combat power increases to 7250 m, but the additional drag of the intakes is so high, that by this increase of 700 m the speeds of the
internal intakes are barely achieved or above 9000 m only slightly exceeded. Below full throttle altitude the speed loss is about
5 - 17 mph (24 - 27 km/h). Hereby it has been shown, that the use of the Fw 190 with external intakes in this variant gives no advantages.
When looking at the speed values recorded here it has to be observed, that the aircraft had no weapons installed and all gun ports (incl. MG 17) had been sealed. By the
installation of the 2 MG 17 in front of the wind shield as well as the 2 MG 151 in the wing roots the speeds should be reduced by ~ 6 - 7 mph (10 - 12 km/h). |
| 4.a+b) |
Chart 5 shows the flown climb performances with internal and external intakes with a take off weight of 7,874 lbs (3575 kg).
Up to about 5 km altitude the climb performance plots are not clearly supported by the measured points due to flying difficulties. The boost drop off altitudes for
the high altitude supercharger gear are 5850 m with the internal intakes and 6250 m for the external intakes, so that the increase in level flight is 700 m and
1000 m respectively. The service ceiling is also influenced only slightly by the external intakes, an increase of 300 m from 11600 to 11900 m results. |
| 5.a) |
The highest cylinder temperatures were recorded in climbs with combat power and fully opened split flaps at cylinder 1. With the production fan at the reversal altitude of ~ 7000 m a
temperature tzyl 1 = 235 ° on the hottest European summer day (cina + 15°) results. The short term temperature limit of 240° is therefore not exceeded.
With the oil cooler F 20750 as used up to now the oil intake temperatures into the engine at the temperature reversal height of 8000 - 8500 m have been determined as
tÖME = 82° (based on the hottest summer day, cine + 20°). The permissible maximum has been given as 85° also for the F-engine by the manufacturer, so
that this cooler meets the requirements in Europe. |
| 5.b) |
During climbs with the variable fan, higher temperatures were recorded due to the functional defects, namely for tzyl 1 = 242° and for tÖME = 84°.
The plotted values can be taken from the charts 6 and 7. |
| 6.a,b,c) |
The cooling pressure drop Δ p+) and the pressures in front of the engine pv+) in climbs in the conditions 6a-c of the program are shown in the charts
8 - 10. A comparison shows that by the installation of the external intakes, and thereby the omittance of the air intake from the ram pressurized compartment, Δ
p+) and pv+) are increased by 10 - 15 mm water column. Through the entire altitude range the pressures in the engine are considerably smaller with the
variable fan than with the production fan because of the already mentioned reasons. Below the pressures recorded in 1000 and 10000 m altitude. |
|
Altitude: m |
1000 |
10000 |
|
Pressure: mm water column |
pv+) |
Δ p+) |
pv+) |
Δ p+) |
|
Variable fan, internal intakes |
435 |
350 |
260 |
225 |
|
Production fan, internal intakes |
510 |
405 |
270 |
235 |
|
Production fan, external intakes |
525 |
420 |
280 |
245 |
| 7) |
Chart 11 shows a summary of the pressures pv+) and Δ p+) as obtained in level flight with combat and take off power in
comparison to ram pressure. The ram pressure utilization calculated from that equals ~ 68 % while the ram pressure utilization calculated from the difference between
the full throttle altitude obtained in level flight at combat power and the full throttle altitude without ram (given by the engine manufacturer as 5500 m) is ~ 60 %. An improvement
of these values can be expected with the now installed fan V035. |
| 8) |
Generally the cylinder temperatures measured with closed split flaps in level flight at combat power near sea level are very low. The highest value at the hottest cylinder for a European
summer day is only 157°, while all other heads show temperatures between 130 - 145° (see chart 12). Already for European conditions difficulties due to overcooling of the
engine can be expected, in particular from the installation of a fan with an even higher flow rate. A further reduction in the outlet cross section in order to reduce air flow is not
possible, since, as shown in charts 6 and 13, in climbs under the same conditions the short term temperature limits are almost reached. |
| 9) |
Faults detected twice so far at the pendulum valve and the KG resulted in a performance loss or a sudden engine stop in 9000 - 9500 m altitude after a prior indication at about 7000 m
in the form of strong shaking and rough running. A further complaint is the very high sensitivity of boost (Kommandogerät) towards the throttle lever position, whereby the
correct setting of a certain power is made very hard. Constant complaints were found with the exhaust jets and the exhaust jet mounts in their current version. The jets get lose at
the cylinder flanges and the mounts break, so that jets repeatedly fall out when opening the engine cowling.
Due to the tank vent pendulum valves getting stuck during a flight, the engine was put under high pressure and since then is very oil untight. This could not be remedied so far.
In flight at combat power ~ 7 - 8 liters of foam develop in the oil tank, so that with too much oil in the tank oil gets spilled through the venting. The maximum filling amount is going
to measured exactly. |
|
