Editing Boeing B-17 Flying Fortress (section)

=== RAF use ===
[[File:Royal Air Force Boeing Fortress Mk.I.jpg|thumb|RAF Fortress I [[United Kingdom military aircraft serials|serial]] ''AN529'', with [[Heinkel He 111|He 111H]]-style "bathtub" ventral [[Gondola (airplane)|gondola]]]]
The RAF entered World War II without a sufficient supply of modern heavy bombers, with the largest available long-range medium bombers in any numbers being the [[Vickers Wellington]], which could carry {{convert|4500|lb}} of bombs.<ref name="Andrews & Morgan p340">Andrews and Morgan 1988, p. 340.</ref> While the [[Short Stirling]] and [[Handley Page Halifax]] became its primary bombers by 1941, in early 1940, the RAF agreed with the U.S. Army Air Corps to acquire 20 B-17Cs, which were given the [[British military aircraft designation systems|service name]] Fortress Mk.I. Their first operation, against [[Wilhelmshaven]] on {{Nowrap|8 July}} 1941 was unsuccessful.<ref name="Yenne.p23" /><ref name="Chant" /> On {{Nowrap|24 July}} three B-17s of [[No. 90 Squadron RAF|90 Squadron]] took part in a [[German battleship Gneisenau#Air attacks in Brest|raid on the German capital ship Gneisenau]] and [[German cruiser Prinz Eugen|Prinz Eugen]] anchored in [[Brest, France|Brest]] from {{cvt|30000|ft}}, to draw German fighters away from 18 [[Handley Page Hampden]]s attacking at lower altitudes, and in time for 79 Vickers Wellingtons to attack later with the German fighters refueling. The operation did not work as expected, with 90 Squadron's Fortresses being unopposed.<ref name="Chorlton p38">Chorlton ''Aeroplane'' January 2013, p. 38.</ref><ref name="hardest p122-3">Richards 1995, pp. 122–23.</ref>{{sfn|Garzke|Dulin|1985|pp=159–60}}

By September, the RAF had lost eight B-17Cs in combat and had experienced numerous mechanical problems,<ref group=Note>problems the RAF found included the tendency to burn when hit, icing problems, crew fatigue due to altitude, oxygen system failures</ref> and [[RAF Bomber Command|Bomber Command]] abandoned daylight bombing raids using the Fortress I because of the aircraft's poor performance. The experience showed both the RAF and USAAF that the B-17C was not ready for combat, and that improved defenses, larger bomb loads, and more accurate bombing methods were required. However, the USAAF continued using the B-17 as a day bomber, despite misgivings by the RAF that attempts at daylight bombing would be ineffective.<ref name="Weigley.338" />

As use by Bomber Command had been curtailed, the RAF transferred its remaining Fortress Mk.I aircraft to [[RAF Coastal Command|Coastal Command]] for use as a long-range maritime patrol aircraft.<ref name="Stitt 1" /> These were augmented starting in July 1942 by 45 Fortress Mk.IIA (B-17E) followed by 19 Fortress Mk II (B-17F) and three Fortress Mk III (B-17G). A Fortress IIA from [[No. 206 Squadron RAF]] sank [[U-627]] on {{Nowrap|27 October}} 1942, the first of 11 U-boat kills credited to RAF Fortress bombers during the war.<ref name="Wynn.93" />

As sufficient Consolidated Liberators finally became available, Coastal Command withdrew the Fortress from the Azores, transferring the type to the meteorological reconnaissance role. Three squadrons undertook Met profiles from airfields in Iceland, Scotland, and England, gathering data for vital weather forecasting purposes.

The RAF's [[No. 223 Squadron RAF|No. 223 Squadron]], as part of [[No. 100 Group RAF|100 Group]], operated several Fortresses equipped with an electronic warfare system known as "[[Airborne Cigar]]" (ABC). This was operated by German-speaking radio operators to identify and jam German ground controllers' broadcasts to their [[nightfighter]]s. They could also pose as ground controllers themselves to steer nightfighters away from the [[bomber stream]]s.<ref>{{cite news|url=https://www.telegraph.co.uk/news/main.jhtml?view=DETAILS&grid=&xml=/news/2007/12/13/db1301.xml|archive-url=https://web.archive.org/web/20071214211240/http://www.telegraph.co.uk/news/main.jhtml?view=DETAILS&grid=&xml=%2Fnews%2F2007%2F12%2F13%2Fdb1301.xml|url-status=dead|archive-date=14 December 2007|title=Obituaries: John Hereford|newspaper=[[The Daily Telegraph]]|date=13 December 2007|access-date=8 July 2021}}</ref>