Boeing C-97

Boeing C-97 Stratofreighter
Boeing C-97 "Stratofreighter"
Type:	military transport aircraft
Design country:	United States
Manufacturer:	Boeing
First flight:	November 9, 1944
Commissioning:	1947
Production time:	1944 to 1951
Number of pieces:	77

The Boeing C-97 Stratofreighter (German: Stratosphärenfreighter ), also Boeing 367 , was a military long-haul transport aircraft built from 1944 and made in the USA , designed as a four-engine propeller aircraft with piston engines . The Boeing 377 Stratocruiser long-haul passenger aircraft was developed based on the Boeing C-97 .

Development and production

The C-97 was a further development of the Boeing B-29 long-range bomber and combined the airframe of the B-29 with the large cross-section of a double-deck fuselage. The first flight took place in 1944; the first three machines were only used for test purposes and were not used for military purposes during the war.

When designing the C-97, only the fuselage was redesigned and the engine changed; the structure and tail units were taken over from the B-29. From the seventh machine on, the larger vertical stabilizer and the engines of the Boeing B-50 Superfortress were used.

The Stratofreighter could transport up to 134 fully equipped soldiers instead of cargo or be used for ambulance transport with 83 stretchers.

production

The first two C-97s were accepted by the USAAF in late 1943 and early 1944.

A total of 77 copies of the C-97 were made.

After the end of the war, the civilian passenger aircraft B-377 Stratocruiser was derived from the C-97 . Due to the strong competition, in particular from the Lockheed Constellation and the Douglas DC-6 , only 56 pieces were produced. A further 811 machines were completed as Boeing KC-97 ¹⁾ air refueling aircraft , many of which were later converted back into C-97 transporters.

¹⁾ The version as a tanker aircraft KC-97 is sometimes incorrectly referred to as the "Stratotanker". According to all reputable sources (including Boeing and USAF), however, the KC-97 Stratofreighter is also called. The name Stratotanker only bears the jet-powered successor model Boeing KC-135 .

→ Main article : Boeing KC-97

Acceptance of the C-97 by the USAF 1945–1951:

year	1943	1944	1945	1946	1947	1948	1949	1950	1951	TOTAL
XC-97	1	2								3
YC-97 / A / B			2	1	6th	1				10
A.						3	13	34		50
C.									14th	14th
TOTAL	1	2	2	1	6th	4th	13	34	14th	77

Modifications to the C-97:

year	out	1960	1961	1962	1963	1964	1965	1966	1967	1970	TOTAL
D.				1	2						3
E.	KC-97E	1									1
F.	KC-97F			5					1		6th
G	KC-97G				100	66	7th	13	1		187
YC-97K					1	1					2
K					12	2		5	7th	2	28
HC-97G						19th	9				28
TOTAL		1	0	6th	115	88	16	18th	9	2	255

In 1953 the three KC-97A were converted into C-97A. Furthermore, in 1955 two KC-97G were used to convert into YC-97J and in 1959 a YC-97 into a C-97F. During the Korean War, six C-97A and the YC-97B were converted into seven C-97Ds, including three VC-97Ds.

Versions

Boeing YC-97 45-59590 with the lower vertical tail of the B-29 (1947)

Boeing C-97A Stratofreighter 49-2607 of the Minnesota Air Guard (1960)

Boeing C-97A Stratofreighter (USAF_Wiesbaden-Erbenheim 1955)

Boeing C-97G at the Pima Air & Space Museum in Tucson . The machine was registered under the Red Cross flag as HB-ILY with the former Swiss Balair for relief flights to Biafra ; in use from 1969 to 1970.

The versions of the KC-97 tanker aircraft not mentioned here are listed in the main article Boeing KC-97 . These are: KC-97E, KC-97F, EC-97G, KC-97G, GKC-97G, JKC-97G, HC-97G, KC-97H, KC-97L.

XC-97

Prototype, three were built.

YC-97

Pre-production machine as a transporter, six were built.

YC-97A

Pre-production machine as a troop transport, three were built.

YC-97B

Pre-production aircraft as a passenger aircraft with 80 seats, later renamed the C-97B, classified as the C-97D in 1954, retired on December 15, 1969.

C-97A

Production version as a transporter with 2425 kW Pratt & Whitney R-4360-27 engines, 50 were built.

KC-97A

Conversion of three C-97A to tanker aircraft . After successful tests, converted back to the C-97A.

C-97C

Series version with reinforcement of the cargo floor and minor changes to the instrumentation and radio system, 14 units built. Machines used for transporting wounded wounds during the Korean War from 1950 to 1953 were designated as MC-97C.

VC-97D

Conversion of three C-97A as VIP transporters and flying command posts.

C-97E

KC-97E converted into transporters.

C-97F

KC-97F converted into transporters.

C-97G

135 KC-97G converted into transporters.

YC-97J

Equipping two KC-97G with four Pratt & Whitney YT34-P-5 turboprops, each 4250 kW. Although successful, other modifications were canceled in favor of the Boeing KC-135 .

C-97K

27 KC-97G converted into troop transports.

Incidents

• On 30 November 1970 an was Boeing 707-373C of Trans World Airlines ( aircraft marks N790TW) at Tel Aviv-Lod the Start initiated at a cargo flight. At the same time an empty, unlit C-97K Stratofreighter of the Israeli Air Force (4X-FPS / 037) was towed over the runway . Despite an attempt to abort take-off , both aircraft collided and caught fire. The three-person crew of the TWA machine and two people on the ground were killed.

Technical specifications

Parameter	Data
crew	4th
length	33.7 m
span	43.1 m
height	11.7 m
Wing area	161.1 m²
Elongation	11.5
Empty mass	37,410 kg
Max. Takeoff mass	79,370 kg
Engines	four radial engines Pratt & Whitney R-4360 -59 with 3,500 HP each (approx. 2,600 kW)
Top speed	603 km / h
Service ceiling	10,670 m
Range	6,920 km

See also

• List of aircraft types

literature

• Gordon Swanborough and Peter M Bowers: United States Military Aircraft since 1909. Putnam Aeronautical Books, London 1989, ISBN 0-85177-816-X .
• Peter M Bowers : Boeing Aircraft since 1916. Putnam Aeronautical Books, London 1989, ISBN 0-85177-804-6 .
• Leonard Bridgman (Ed.): Jane's All The World's Aircraft, 1952-53. Sampson Low, Marston & Company, London 1964.
• Martin Bach: Boeing 367 Stratofreighter, Boeing 377 Stratocruiser, Aero Spacelines Guppies. NARA Verlag, Allershausen 1996, ISBN 3-925671-18-8 .

Web links

Commons : Boeing C-97 Stratofreighter  - Collection of images, videos and audio files

• KC-97 in the National Museum of the United States Air Force
• Airworthy KC-97 Angel of Deliverance
• C-97 / KC Stratofreighter. In: History. Boeing, 2017, accessed January 2, 2018 . 

Individual evidence

1. ↑ Bowers, p. 353
2. ↑ Swanborough / Bowers, pp. 125-127.
3. ↑ Jane's 1952, p. 183
4. ↑ Bach, p. 7
5. ↑ Statistical Digest of the USAF 1946, p. 94; 1947, p. 118; 1948, p. 16; 1949, p. 164 f .; 1951, p. 159
6. ^ Gordon Swanborough, Peter M. Bowers : United States Military Aircraft since 1909. Putnam Aeronautical Books, London 1989, ISBN 0-85177-816-X , pp. 125–129.
7. ↑ Statistical Digest of the USAF 1960–1972, table "Gains and Losses"
8. ↑ Statistical Digest of the USAF 1950–1972, table “USAF Aircraft Gains and Losses”; 1956, p. 117 ff., 1961, p. 97 ff.
9. ^ Bowers, p. 357
10. ^ Bowers, p. 358
11. ↑ Bowers, p. 362
12. ^ Bowers, p. 364
13. ↑ Accident report collision TLV: B-707 N790TW. Aviation Safety Network , accessed February 16, 2019.
14. ↑ Accident report collision TLV: C-97K 4X-FPS / 037. Aviation Safety Network, accessed February 16, 2019.