B-17 vs B-24

The B-17 and the B-24 inevitably invited comparison. Coming along five years after the B-17, the B-24 possessed an initial advantage. It carried a larger bomb load than the B-17, and could carry the load farther, with a crew of the same size — ten men. Listed in the charts originally as having a range of 2,850 miles with a 2,500- pound bomb load, experience showed that it did have a longer reach than any other competing plane. It was this advantage that gave the B-24 the call over the B-17 for service in CBI and SWPA, where Kenney's Fifth Air Force used it for the 2,400-mile round trip attacks on Balikpapan in 1944, and where regularly, if less spectacularly, it extended the coverage of overwater search.

Against the German Air Force, however, combat experience showed the plane to be lacking in armament and armor. Attempts to remedy these and other shortcomings increased the weight of the plane and altered flight characteristics in such a way as to render it less stable. Lt. Gen. James H. Doolittle, commanding the Eighth Air Force, made his preference for the B-17 clear in a letter of January 1945. By that date the increased range of the B-17 some time since had robbed the B-24 chief advantage. Against the Luftwaffe, the capital enemy, the rugged and steady B~i7 remained the natural pick.

The B-24 differed greatly from the B-17. Its 110 foot wing was a radical departure in airfoil types at the time. Other differences included hydraulically operated wing flaps,bomb bay doors, and power brakes. It was the first American heavy bomber to operate with a retractable landing gear, and unlike the B-17, its tail assembly had two vertical fins and rudders. Its service ceiling was estimated to be 31,500 feet and it could carry amaximum bomb load of 8960 pounds. The engines were four Pratt & Whitney-1830 engines which made the gross weight of the airplane close to 41,000 pounds.

The B-17, although the first of the country's heavy bombers, was not produced in as great quantity as was the B-24. Between January 1940 and 31 August 1945 the AAF accepted a total of 12,692 B-17s and 18,190 B-24s. The peak AAF inventory for B-17 was 4,574 in August 1944, and for B-24, 6,043 September 1944. The maximum number of overseas combat groups was thirty-three for the B-17 in September 1944 and forty-five and one-half for the B-24 in June 1944. Both planes were used in virtually every theater of war, but, in general, the B-i7*s were concentrated in the European and Mediterranean theaters and the B-24's in the Mediterranean and Pacific theaters.

B-24 performance problems, coupled by the fact that B-17 production was to taper off prior to B-24 production, prompted the Army Air Force (AAF) to investigate the combat effectiveness of the plane in comparison to the B-17. A comparative analysis conducted in the spring of 1944 by the AAF Operations and Requirements Division concluded that “it would be desirable to increase B-17 production and decrease that of the B-24, because the former airplane is a much more effective combat weapon.”

This recommendation was based on statistical comparisons:

1. Statistical data compiled on the utilization of both planes showed that the B-17 was easier to maintain and therefore more available for combat.
2. Statistical data on time from aircraft acceptance to delivery in theater showed that the B-17’s spend only half as much time in modification centers thus are availableat the theaters in a shorter time.
3. Use of B-17 combat sorties, versus B-24, resulted in a 40% savings in personneland material.
4. The average man-hours expended in producing and modifying one B-24 weregreater than for a B-17.
5. Statistical comparisons done on loss rate per sortie showed that the B-17 had a 35% longer combat life than the B-24.

Another study was conducted in the fall of 1944 by the AAF Unit Training Division. In the final report,Colonel Walker, Chief of the Unit Training Division, states the following: "The extensive use of the B-24 is inconsistent with the blunt fact that it is the most extravagant killer of any airplane in the AAF. Since Pearl Harbor through September 1944, B-24 accidents in the U.S. have resulted in 2,188 fatalities. In the first 9 months of 1944, B-24’s did only 6% of total flying in the U.S. but accounted for 26% of all fatalities. They flew 5% less than B-17’s but had 105% more fatalities and 85% more wrecks. Had the B-24 had as good accident rate as the B-17 during the period 7 December 1941 through September 1944, there would have been a saving of 230 aircraft wrecked, 904 lives, and approximately $60,000,000.”

Although some in the AAF were not too enthused about the B-24’s performance, theRoyal Air Force (RAF) preferred it to the B-17. Unconvinced of the value of daylight precision bombing with a four-engine aircraft, the RAF was sold on the “safer” night area bombing. They also believed that the B-17 would make a satisfactory night bomber but pointed out that its firepower was wholly inadequate for protection during daylight missions, and that its bomb capacity was too light to warrant the raduis of action of which it was capable. However, they considered the B-24 a superior night bomber because ofits greater bomb load and larger fuselage which made possible the installation of increased defensive armament. The RAF also believed that the B-24 was useful for coastal patrol for locating and destroying enemy submarines and the German Focke-Wulf patrol bombers. Even though it had less defensive fire and high altitude speed than the B-17, the British felt that the B-24 was still superior to the German bomber. Thus, they preferred the B-24 and even named her the "Liberator".

In a letter dated 14 Feb 1944,Maj Gen Doolittle, 8th Air Force Commander, requested to Lt Gen Spaatz, U.S. Strategic Forces in Europe Commander, that B-24’s be modified and redesigned in order to correct performance problems that the plane had been experiencing. He stated that the problems were a result of the efforts taken to increase the ability of the B-24 to protect itself by increasing its armament. He also explained that it was difficult to motivate his crews because the pilots flying the B-24’s knew that the plane was not performing as well as the B-17.