SUBJECT:      Results of Flight Tests

SECTION:      Flight

SERIAL No.   Eng-47-1652-A

A.    Purpose

        1.   To report results of flight tests on P-47D-10 airplane, AAF No. 43-75035 run at the manufacturer's plant. Airplane equipped with Pratt & Whitney R-2800-63 engine with water injection; standard Curtiss 714-1C2-12 propeller; type A-17 turbo regulator. Airplane ballasted to simulate the following conditions: Six .50 caliber guns; 300 rounds per gun; 305 gallons gasoline; 15 gallons water; 14 pounds pyrotechnics. In this condition the gross weight was 13,234 pounds with a C.G. wheels up, of 29.63 percent M.A.C. Mixture auto-rich; throttle wide open on all tests. Horsepower data obtained with torquemeter.

B.    Results.

        1.   High speed: Intercooler and oil cooler flap neutral, cowl flaps closed; flaps and gear up; 2700 R.P.M. with water injection.

Altitude Ft.	Manifold Pressure "Hg.	Torque Brake Horsepower	Turbo RPM	Exhaust Back Press. "Hg.	Carb. Air Temp. °C	True Speed MPH
0	56	2210	7,200	36.0	32.0	333
5,000	56	2265	9,400	33.2	27.0	353
10,000	56	2315	11,600	31.4	23.0	372
15,000	56	2335	13,850	30.3	23.0	390
20,000	56	2325	16,200	30.5	26.0	406
25,000	56	2265	18,650	32.5	33.0	421
30,000	56	2225	21,400	35.7	43.0	433
31,000	56	2220	22,000	36.5	46.0	435
33,000	50.5	2020	22,000	32.0	39.0	430
35,000	45.8	1740	22,000	30.0	32.0	422
38,000	39.0	1550	22,000	25.3	23.0	404

        2.   Climbs: Cowl flaps wide open; intercooler and oil cooler flaps wide open; flaps and gear up; 2700 RPM with water injection.

Altitude Ft.	Manifold Pressure "Hg.	Torque Brake Horsepower	Turbo RPM	Carb. Air Temp. °C	Exhaust Back Press. "Hg.	Rate of Climb Ft/Min.
0	56	2200	7,300	26.0	37.0	2870
5,000	56	2285	10,400	24.5	35.5	2810
10,000	56	2320	12,850	23.5	34.5	2680
15,000	56	2330	15,100	24.0	34.0	2460
20,000	56	2320	17,200	27.5	34.5	2180
* 25,000	56	2280	20,000	34.5	36.5	1860
** 28,000	53.5	2150	22,000	40.0	36.5	1520
30,000	51	2070	22,000	37.5	35.0	1400
34,000	43.5	1780	22,000	28.5	30.0	950
38,000	37.5	1520	22,000	20.0	25.0	500

        * Critical altitude for 56 inches manifold pressure due to A-17 type turbo-regulator.

        ** Critical altitude for 22,000 turbo R.P.M.

             If the turbo regulator would have allowed 56 inches manifold pressure to turbo critical the follwoing vaules would have been obtained.

Altitude Ft.	Manifold Pressure "Hg.	Torque Brake Horsepower	Turbo RPM	Carb. Air Temp. °C	Exhaust Back Press. "Hg.	Rate of Climb Ft/Min.
27,500	56	2260	22,000	44.0	38.5	1680

        3.   Airspeed calibration: Wheels and flaps up.

Indicated Airspeed MPH	Water Column Airspeed MPH	Calibrated Airspeed MPH	Position Error MPH	Alitimeter Correction Ft.
140	140.5	145	-4.5	+  25
160	160.5	165.5	-  5.0	+  40
180	180	186.0	-  6.0	+  60
200	199.5	206.0	-  6.5	+  75
220	220	228	-  8.0	+  90
240	240.5	249.5	-  9.0	+105
260	260.5	271.0	-10.5	+120
280	282	293	-11.0	+140
300	302	314	-12.0	+160

C.    Discussion

        1.   The total water supply was sufficient for only ten minutes flying allowing continuous war emergency power climbs from sea level to 24,000 feet.

        2.   In climb, the A-17 type turbo regulator drops the manifold pressure before limiting turbo R.P.M. is reached. If this regulator allowed 56 inches Hg. to the turbo critical altitude, an increase of approximately 100 feet per minute rate of climb in the region from 26,000 to 28,000 feeet would be obtained.

        3.   A forced landing caused the acceptance tests to be discontinued temporarily. Results of climb tests above 35,000 feet, a cruising power calibration, and take-off tests will be reported as an addendum to this report.