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Flight Tests on the Lockheed
P-38J Airplane, AAF NO. 43-28392
In level flight at 19800 ft., the critical altitude for 70" hg. manifold pressure, 3000 RPM, and 26,300 limiting turbo RPM, a maximum speed of 419 MPH was attained. At this altitude a high speed of 402.5 MPH was attained at 60" Hg. manifold pressure. At 24000 ft., the critical altitude for 60" Hg. manifold pressure, 3000 RPM, and 26,300 limiting turbo RPM, a high speed of 413 MPH was attained.
At sea level a maximum rate of climb of 4040 ft/min was attained at 70" Hg. manifold pressure and a rate of climb of 3570 ft/min at 60" Hg. manifold pressure and 3000 RPM. The service ceiling of the airplane was 39,000 ft., and the absolute ceiling was 39,700 ft.
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Flight tests were conducted on the P-38L airplane, AAF No. 44-25092, at Wright Field, Dayton Ohio and Miami Depot, Miami, Florida in order to obtain a performance and range check of the data given as tentative figures in Pilot's Flight Operating Instructions, AN 01-75-1.
Level Flight Performance
The following speed data was obtained with the airplane in the clean configuration. Data is corrected to weight at altitude as given in Figure 4, Appendix A and NACA standard day conditions.
a. True speed at sea level at war emergency power, 1530 BHP and 3000 RPM, was 342 MPH.
b. True speed at critical altitude, 26,000 feet, at war emergency power, 1495 BHP and 3000 RPM, was 416 MPH.
c. True speed at sea level at military power, 1395 BHP and 3000 RPM, was 331 MPH.
d. True speed at critical altitude, 26,200 feet, at military power, 1385 BHP and 3000 RPM, was 408 MPH.
e. True speed at sea level at normal rated power, 1110 BHP and 2600 RPM, was 302 MPH.
f. True speed at critical altitude, 32,200 feet, at normal rated power, 1138 BHP, was 400 MPH.