550th Strategic Missile Squadron

History

World War II

Initial activation and training

The squadron was first activated at Davis-Monthan Field, Arizona as the 550th Bombardment Squadron, one of the four original squadrons of the 385th Bombardment Group. The following month it moved to El Paso Army Air Field, Texas, but did not receive a full complement of personnel and begin training with Boeing B-17 Flying Fortress until it moved to Geiger Field, Washington in February 1943. It completed its training and began deploying to the European Theater of Operations. The air echelon staged through Kearney Army Air Field, Nebraska in May 1943 and ferried its Flying Fortresses to England via the northern ferry route. The ground echelon left for the port of embarkation and sailed on the on 1 July 1943.

Combat in Europe

The squadron assembled at its combat station, RAF Great Ashfield, England, and began participating in the strategic bombing campaign against Germany, flying its first combat mission on 17 July 1943.

Strategic industrial targets for the squadron in Germany included the AGO Flugzeugwerke factory at Oschersleben and the Henschel Flugzeugwerke factory at Marienberg; a battery manufacturing plant at Stuttgart, oil refineries at Ludwigshafen and Merseburg and rail marshalling yards at Munich and Oranienburg. It also attacked Luftwaffe bases at Beauvais/Tille Airfield and Chartres Airfield, France.

The squadron was occasionally diverted from the strategic bombing mission to perform air support and interdiction missions. It struck coastal defenses in June 1944 in preparation for Operation Overlord, the Normandy invasion, and on D-Day attacked transportation chokepoints and marshalling yards. In late July, it attacked enemy positions to support Operation Cobra, the breakout at Saint Lo. In late December 1944 and early January 1945, it carried out attacks on German fortifications and transportation to support forces engaged in the Battle of the Bulge. As the Allies made their final thrust through France into Germany, it attacked troop concentrations and communications targets.

The squadron flew its last mission on 20 April 1945. Following V-E Day, the squadron transported prisoners of war from Germany and flew six missions dropping food supplies in the Netherlands. The air echelon began ferrying its aircraft back to the United States on 19 June and all bombers had departed Great Ashfield by the end of the month. The ground echelon of the squadron left Europe in August 1945, sailing on the RMS Queen Elizabeth and the squadron was inactivated in the United States at Sioux Falls Army Air Field, South Dakota on 28 August 1945.

Air Force reserve

On 15 September 1947, the squadron was activated under Air Defense Command (ADC) in the reserve at Selfridge Field, Michigan. The squadron does not appear to have been fully manned or equipped during this period. The 550th was inactivated when ConAC reorganized its reserve units under the wing base organization system in June 1949. The squadron's personnel and equipment were transferred to elements of the 439th Troop Carrier Wing.

Intercontinental ballistic missile squadron

The squadron was redesignated the 550th Strategic Missile Squadron and organized at Schilling Air Force Base, Kansas in April 1961 as a Strategic Air Command (SAC) SM-65F Atlas intercontinental ballistic missile launch squadron and assigned to the 310th Bombardment Wing. The squadron was assigned twelve missiles, based in a 1 x 12 configuration: twelve independent widely dispersed launch sites comprised the missile squadron. In June 1962, the first operational sites for the Atlas F ICBMs were accepted by SAC and in September the squadron was declared operational.

The Atlas F was the final and most advanced version of the Atlas and was stored in a vertical position inside underground concrete and steel silos. When stored, the Atlas F sat atop an elevator. If a missile was placed on alert, it was fueled with RP-1 (kerosene) liquid fuel, which could be stored inside the missile for extended periods. If a decision was made to launch the missile, the missile was raised to the surface and the liquid oxygen tank was filled. The launch would occur shortly after completion of this process. The exposure on the surface that this procedure entailed was the great weakness of the Atlas F. It was exposed and vulnerable during this time. The Titan II and Minuteman missiles could be launched from within their silos, thereby eliminating this vulnerability. Also, since the Titan did not use a cryogenic fuel or oxidizer, and the Minuteman was a solid fuel rocket, they could be stored fully fueled and ready to launch within a very few minutes.

The squadron operated twelve missile sites of one missile at each site (12 total): :: 550–1 : 2.8 mi S of Wells, Kansas : :: 550–2 : 3.2 mi W of Abilene, Kansas : :: 550–3 : 2.5 mi WNW of Chapman, Kansas : :: 550–4 : 5.1 mi W of Elmo, Kansas : :: 550–5 : 7.0 mi SSE of Lindsborg, Kansas : :: 550–6 : 1.8 mi ENE of Mitchell, Kansas : :: 550–7 : 1.5 mi NW of Carneiro, Kansas : :: 550–8 : 2.3 mi ENE of Wilson, Kansas : :: 550–9 : 4.4 mi NNW of Beverly, Kansas : :: 550–10 : 1.5 mi ENE of Tescott, Kansas : :: 550–11 : 8.7 mi WSW of Aurora, Kansas : :: 550–12 : 3.7 mi NE of Minneapolis, Kansas :

During the Cuban Missile Crisis, on 20 October 1962, SAC directed that the squadron's missiles that were not on alert for modifications be placed on alert status "as covertly as possible." Training was suspended and missiles being used for operational training were to be placed on alert as soon as liquid oxygen became available. From 3 November the number of alert missiles was reduced until on 29 November the number was the same as before the crisis. As tensions eased, on 15 November normal training resumed.

On 1 December 1964, the first Atlas F missile at Schilling was removed from alert status. The squadron became nonoperational on 11 March 1965 and was inactivated on 25 June 1965.

Lineage

• Constituted as the 550th Bombardment Squadron (Heavy) on 25 November 1942 : Activated on 1 December 1942 : Redesignated 550th Bombardment Squadron, Heavy on 20 August 1943 : Inactivated on 28 August 1945
• Redesignated 550th Bombardment Squadron, Very Heavy on 25 August 1947 : Activated in the reserve on 15 September 1947 : Inactivated on 27 June 1949
• Redesignated 550th Strategic Missile Squadron (ICBM-Atlas) and activated on 22 July 1960 (not organized) : Organized on 1 April 1961 : Inactivated on 25 June 1965

Assignments

• 385th Bombardment Group, 1 December 1942 – 28 August 1945
• Second Air Force, 15 September 1947
• Tenth Air Force, 1 July 1948
• First Air Force, 15 August 1948
• Tenth Air Force, 1 December 1948 – 27 June 1949
• Strategic Air Command, 22 July 1960 (not organized)
• 310th Bombardment Wing (later 310th Strategic Aerospace Wing), 1 April 1961 – 25 June 1965

Stations

• Davis-Monthan Field, Arizona, 1 December 1942
• El Paso Army Air Field, Texas, 4 January 1943
• Geiger Field, Washington. 1 February 1943
• Great Falls Army Air Base, Montana, 11 March – 7 June 1943
• RAF Great Ashfield (AAF-155), England, 29 June 1943 – 6 August 1945
• Sioux Falls Army Air Field, South Dakota, 14–28 August 1945
• Selfridge Field (later Selfridge Air Force Base), Michigan, 15 September 1947 – 27 June 1949
• Francis E. Warren Air Force Base, Wyoming, 1 October 1960
• Schilling Air Force Base, Kansas, 1 April 1961 – 25 June 1965

Aircraft and missiles

• Boeing B-17 Flying Fortress, 1942–1945
• Convair SM-65F (later HGM-16F) Atlas, 1961–1965

Awards and campaigns

References

Notes

; Explanatory notes

; Citations

Bibliography

References

1. Maurer, ''Combat Squadrons'', p. 654
2. Watkins, pp. 70-71
3. Freeman, p. 288
4. Freeman, p. 254
5. Maurer, ''Combat Units'', pp. 272-273
6. The unit carried out attacks on industrial targets, including communications centers as well as [[air base]]s in Belgium, France, Germany, the Netherlands, Belgium and Norway, striking targets as far away as Poland. On 17 August 1943, the squadron participated in an [[Schweinfurt–Regensburg mission. attack on the Messerschmitt aircraft factory at Regensburg]], which involved a long flight over heavily defended enemy territory with little protection from escorting fighters.{{efn. Half the fighter escorts missed the scheduled rendezvous, the other half returned to England at the limit of their fuel supplies before the heaviest [[interceptor aircraft
7. Freeman, p. 142
8. ''See'' Maurer, ''Combat Squadrons'', pp. 651-652 (no aircraft listed as assigned during this period).
9. Ravenstein, pp. 236-237
10. Kipp, ''et al''., pp. 62-63, 66, 70-71
11. SAC Missile Chronology, p. 48
12. Lineage, including assignments, aircraft and missiles, through March 1963 in Maurer, ''Combat Squadrons'', p. 654.
13. Ravenstein, pp. 158-159
14. Station number in Anderson.
15. Station information through March 1963 in Maurer, ''Combat Squadrons'', pp. 654, except as noted.