Goddard began tests of two propellant pumps, called A and D. These were selected for use in four proving-stand tests (P1 to P4), from January 6 to February 28, 1939. From these tests it was concluded that a small chamber, or gas generator, producing warm oxygen gas, should be developed for operating the turbines. References: 482 .

Engine used 29 lb liquid oxygen; 45 lb gasoline; produced 671 lb of lift for 12 sec, with jet velocity of 4820 ft/sec; oxygen 2.15 lb/sec; gasoline, 2.28 lb/sec; mixture ratio 0.94. Over 24 pump tests were completed by the time of the last run on February 28. References: 482 .

Series P section B was a series of tests by Goddard in development of a gas generator to run turbines. Through April 28 a series of eleven static tests (Pa-k) of a new gas generator was made near the shop. The best form developed ran steadily for 10 sec at 180 psi for 250-psi tank pressures, with the rate of flow of oxygen at 0.49 lb/sec. References: 482 .