Myth #1: There was a prototype XB-17

Boeing built a prototype four-engine bomber to meet Army specification 98-201 dated July 18, 1934, and Boeing designated it as its Model 299. As a civil aircraft, it was issued a Bureau of Air Commerce identification number of X13372 on July 16, 1935. The prototype Model 299 was destroyed in a crash on October 30, 1935, while undergoing a test series for the Air Corps. It was never purchased by the government and thus was never a military aircraft. If it had been purchased, it would have been designated as the XB-17.

Interestingly, its competitor, the prototype Douglas DB-1, won the contract and was unenthusiastically awarded a production contract by the Air Corps but the prototype was never purchased by the military and thus, there was also never an “XB-18.” What Douglas did with its prototype DB-1 is unknown.

In the scheme of things, Boeing did get a contract to build its Model 299, and it got it ahead of Douglas. This is perhaps why the B-17 was the B-17 (a number ahead of the B-18). The Air Corps awarded contract AC 8306 to Boeing for 13 B-17s at $266,751 per airplane on December 18, 1935, and they were assigned FY 1936 serial numbers of 36-149/161. Douglas received contract AC 8307 a month later, on January 28, 1936, for 134 B-18s with later FY 1936 (and FY 1937) serial numbers at a unit cost of $83,990 each.

Myth #2: There was no XB-17

Well, actually, there were at least two XB-17s that were production aircraft set aside for test purposes. B-17F 41-24613 was redesigned as the XB-17F when it was assigned to the NACA for aerodynamic tests. And an 8th Air Force veteran B-17G, s/n 42-39840, was redesignated as the XB-17G in June 1945 and was operated by the U.S. Navy for radar tests at Bedford, Massachusetts, that led the development of the Navy PB-1Ws.

Myth #3: The First Series B-17 Designed for Power Turrets Was the B-17E

Actually, Boeing was designing the B-17C to incorporate remotely fired turrets with a fire control system. According to the definitive AAF Study Development of Aircraft Gun Turrets in the AAF, 1917-1944, Boeing expected to equip the B-17C with retractable upper and lower remote fired gun turrets that were being developed by the Sperry Gyroscopic Co. To quote form page 104 of the study, “…the program of the moment was to arm the B-17C with two waist hand-held .50s mounting computing sights, the upper remote, and the lower with a modified driftmeter sight. Sperry was to provide the sight, computers, flexible shafts, power units, and controller’ Boeing was to build the turret dome or enclosure, the ring gear mounting, gun mounts, and gear trains.” By July 1940, due to delays in the Sperry program, the plan for a complete fire control system for the B-17 was abandoned in favor of locally controlled (manned) gun turrets. Sperry was to build a manned upper turret and a remotely-sighted lower turret for the B-17, but they did not actually get into the airplane until the B-17E series.

Myth #4: The Design Changes That Created the B-17E Were As A Result of RAF Combat Experiences With the B-17C

Superficial histories of the B-17 often state that the changes Boeing designed into the B-17E were mostly as a result of the poor combat performance of the B-17C when it was pressed into service by the British Royal Air Force. While it is true that the twenty B-17Cs, designated as Fortress Is by the RAF, were dismal failures in their combat debut in Europe, the RAF did not put these aircraft into service until July 1941.

The Air Corps was already quite aware of the shortcomings of the B-17B and B-17C as combat aircraft and were working with Boeing to upgrade the design as quickly as possible. As noted above, gun turrets were slated for the B-17Cs, which were actually delivered between July and November 1940, but the turrets weren’t ready. The B-17Ds were delivered by Boeing between February and April 1941. Meanwhile, the first B-17E flew in September 1941, two months after the Fortress Is had been placed in service by the RAF. Major redesign of the B-17 design that produced the B-17E started in May 1940, fourteen months before RAF operations began.

Myth #5: The First 112 B-17Es Had Remotely Controlled Bendix Turrets

You’ll find this error in several notable and otherwise reliable sources on the B-17. Hard to know where this one started, but there was a remotely-sighted and controlled Bendix lower turret on early B-24s and B-25s. But the first 112 B-17Es delivered actually had a remotely-sighted and controlled Sperry turret. But even before the first B-17E was delivered, it was realized that the Sperry remote turret was not a viable defensive weapon. However, the new Sperry ball turret was not yet ready for prime-time. That first batch of B-17Es with the Sperry remote turret were fitted with provisions to mount the Sperry ball turret when it was available, but none of the B-17Es delivered after #112 had provisions to accept the earlier Sperry remote turret. It is telling that only 112 Sperry remote turrets were purchased under contract; no spares were available. That first ball turret B-17E was delivered on January 13, 1942, five weeks after Pearl Harbor so, again, the replacement of the remote turret was not due to combat experience; the Air Corps knew before anyone used the remote turret in combat that it was grossly inadequate. The ball turret, in contrast, was a brilliantly executed work of engineering.

In any event, the remote turrets installed on early B-17Es were Sperry turrets. A bit more in-depth can be found here.

Myth #6: The Sperry Ball Turret Was Retractable on the B-17

You see this one every once in a while. The confusion no doubt comes because the nearly-identical turret as installed on the B-24 was indeed hydraulically retractable. This was required by the tricycle landing gear of the B-24; it was a low-rider.

Myth #7: The Russians Never Had B-17s

The Soviets were eager to obtain B-17s through the Lend-Lease program. The U.S. government wisely declined those requests and never transferred any B-17s to the Red Air Force. However, the Soviets were able to add a few B-17s to its fleet through combat recoveries. The definitive work on the subject is C.F. Geust and G. Petrov’s Red Stars 4: Lend-Lease Aircraft in Russia. The book records that a total of 23 B-17Gs were placed in service with the Soviet air force and they remained in service through at least the late 1940s.

Myth #8: The Army Serial Number Tells What Year the Airplane Was Built

This one is easy but it quite often appears in the media and even official government reports, not only for B-17s but for all AAF aircraft. The U.S. Navy made it simple…all their aircraft were numbered sequentially as Bureau of Aeronautics serial numbers, from number BuNo 1 (Curtiss Model 84) to something like BuNo 170277 (KC-130J). For the Army, it used the fiscal year of purchase as its first two digits, then sequentially assigned serials to aircraft to the various aircraft production contracts. In the way-back days, the federal fiscal year went from July 1 to June 30; thus, FY 1944 aircraft contracts were those aircraft placed under contract from July 1, 1943, through June 30, 1944. The highest serialed B-17 is B-17G 44-85841, delivered on July 28, 1945. As can be seen, though, it was placed on order prior to June 30, 1944.

But, as an aside, there was a FY 1945 contract for B-17s. They were being built by Douglas in July 1945 and had a serial block that began with 45-7001. Though a dozen or more in the serial series were built, none were delivered and all were scrapped with the termination of contracts as the war drew to a close. More here on this little detail of B-17 history.

Of the 46 surviving intact B-17s, 34 are B-17Gs delivered in 1945.

Bonus Myth #9: A B-17 That Does Not Have A Chin Turret Can’t Be a B-17G

I’ll just throw this one in the list because it is often seen out there on Facebook posts. Arguments appear in posts showing photos of B-17s without chin turrets as to whether or not the airplane is a B-17G. As is usually stated somewhere in the comments with the post, all post-war AAF and USAF B-17s had their chin turrets removed along with all their other turrets, guns, and armor. The post-war AAF/USAF B-17 was not a combat aircraft so it had no need for drag-inducing heavy leaky turrets.

Speaking of post-war B-17s, if you’ve read this far you are a B-17 devotee. You should also know this post was actually brought to you by Final Cut: The Post-War B-17 Flying Fortress and Survivors. If you don’t have your copy of the 5th Edition of the book, you should take a look. Actually, you should just go ahead and buy one.