The Petlyakov Pe-8, also known as TB-7 was a Soviet bomber aircraft of World War II, the only four-engined bomber the USSR used during the war.

The USSR had no plans for strategic bombardment, and only a few Pe-8 attacks on Germany were flown, the first in early August, 1941 (only weeks after the German attack on the USSR had started), when aircraft of the 81st Bomber bombed Berlin. Most Pe-8 attacks on Berlin were 'nuisance' bombings involving only a handful of aircraft (e.g. 14 in the first raid). It was used in the strategic bomber role to attack targets in German-held Eastern Europe and as a tactical bomber to support ground forces in the battles of Stalingrad and Kursk. The Pe-8 at first equipped a single bomber wing, the 432 BAP (ON) (432nd Special Bomber Wing) and its reserve unit, the 433nd; they was later reorganized into the 746 and 890 BAP (bomber wing).

The Pe-8's most important claim to fame is flying Soviet foreign minister Molotov and his delegation from Moscow to London and Washington DC and back for talks on the opening of a second front against Nazi Germany (May 19th-Jun 13th, 1942), on the return trip crossing German-controlled airspace without incident.

Only 93 or 96 (including two prototypes) were built from 1936-1944 - older sources claim a number of 81 including prototypes, with production stopping in 1940; this seems to indicate that indeed only replacement aircraft were built after 1940. Some had Charomski M-30 B or M-40 diesel engines and the later aircraft were fitted 1,380 kW (1,850 hp) Shvetsov ASh-82 radials due to low availability of the AM-35A. Neither variant was as successful as the original, the diesel engines giving poorer performance and the radial delivering better performance but often being unreliable. It is a testimony to the soundness the design, however, that the examples which survived WWII were retained in service until the late 1950s despite the availability of the Tu-4. Altogether, the Pe-8, despite suffering from low priority of the strategic bombing role in the USSR military doctrine of its time and problems with the engines, compares well with other four-engined bombers designed in the late 1930s.

From a technical standpoint, the Pe-8 is remarkable because it had defensive machine-gun positions installed in the rear of the inboard engine nacelles. These were deleted when the nacelles were reconstructed for accomodation of the radial engines.

Specifications (Pe-8)

Sources vary on the exact measurements and performance. The values given here must be considered approximate.

General characteristics

• Crew: eleven
• Length: 23.59 m (77 ft 5 in)
• Wingspan: 39.10 m (128 ft 3 in)
• Height: 6.20 m (20 ft 4 in)
• Wing area: 188.7 m² (2,030 ft²)
• Empty: 19,986 kg (43,969 lb)
• Loaded: 27,000 kg (59,400 lb)
• Maximum takeoff: 35,000 kg (77,000 lb)
• Powerplant: 4x Shvetsov AM-35 A inlines, 1,000 kW (1,350 hp) each

Performance

• Maximum speed: 443 km/h (276 mph)
• Range: 3,600 km (2,245 miles)
• Service ceiling: 9,300 m (30,504 ft)
• Rate of climb: 352 m/min (1,154 ft/min)
• Wing loading: 143 kg/m² (29 lb/ft²)
• Power/Mass: 0.14 kW/kg (0.2 hp/lb)

Armament

• 2x 20 mm ShVAK cannons (dorsal and tail turret)
• 2x 12.7 mm UBT machine guns (engine nacelles)
• 1-2x 7.62 mm ShKAS machine guns (nose turret)
• up to 4,000 kg (8,800 lb) of bombs

External links:

http://www.aviation.ru/Pe/#8

Related content

Related development: Tupolev ANT-42

Comparable aircraft:

Designation sequence: Pe-2 - Pe-3 - Pe-4 - Pe-8