Voskhod spacecraft

Voskhod spacecraft

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Voskhod
Voskhod 2 spacecraft
Type	Space capsule
Manufacturer	Korolev
Designed by	Sergei Korolev
Maiden flight	1964
Introduced	1964
Retired	1965
Status	Last 4 flights cancelled
Primary users	Soviet space program
Built	4+
Variants	Vostok spacecraft, Foton

The Voskhod (Russian: Восход, "ascent", "dawn") was a spacecraft built by the Soviet Union's space program for human spaceflight (see Voskhod programme). It was a development of and a follow-on to the Vostok spacecraft.

The craft consisted of a spherical descent module (diameter 2.3 meters), which housed the cosmonauts, and instruments, and a conical instrument module (mass 2.27 tonnes, 2.25 m long, 2.43 m wide), which contained propellant and the engine system.

Design

The Voskhod spacecraft is basically a Vostok spacecraft that has had a backup, solid fuel retro rocket, added to the top of the descent module. The ejection seat was removed and two or three crew couches were added to the interior at a 90-degree angle to that of the Vostok crew position. In the case of Voskhod 2, an inflatable exterior airlock was also added to the descent module opposite the entry hatch. After use, the airlock was jettisoned. There was no provision for crew escape in the event of a launch or landing emergency. A solid fuel braking rocket was also added to the parachute lines to provide for a softer landing at touchdown. This was necessary because, unlike the Vostok, the crew lands with the Voskhod descent module.

In order to create more space inside the descent module, the cosmonaut's ejection seat was removed, meaning that the Voskhod crews would return to Earth inside their spacecraft, unlike the Vostok cosmonauts who ejected and parachuted down separately. The lack of space also meant that the Voskhod 1 crew did not wear space suits. Both crew members wore spacesuits on the Voskhod 2 mission, as it involved an EVA and used an airlock. The second crew member wore a spacesuit as a precaution against the possibility of accidental descent module depressurization. Because the crew was required to land with the descent module, a new landing system to slow the craft was developed. This added a small solid-fuel rocket to the parachute lines. It fired as the descent module neared touchdown, providing a softer landing than did Vostok. A backup solid-fuel retrorocket was added to the top of the descent module. The original Vostok spacecraft only had one liquid fuel retrorocket and no provision for backup. The Vostok did carry enough onboard supplies for a 10-day flight. This would allow for natural orbit decay and reentry if the retrorocket failed. Finally, the Voskhod 2 spacecraft carried a large inflatable airlock that allowed cosmonaut Aleksei Leonov to exit and re-enter the craft.

The airlock carried on Voskhod 2 weighed 250 kg, was 700 mm in diameter, 770 mm high when collapsed for launch. When extended in orbit, the airlock was 2.5 m long. It had an internal diameter of 1.0 m and an external diameter of 1.2 m.

It was carried into orbit by the Voskhod rocket, also developed from the earlier Vostok rocket and ultimately derived from the R-7 ICBM.

Vostok 3KV (1964)

Also known as Voskhod. Adaptation of the Vostok spacecraft for three cosmonauts. This version flew twice, on 6 October 1964 unmanned (as Cosmos 47) and on 12 October 1964 manned as Voskhod 1.

Basic data

Crew size: 3 (without spacesuits)
Endurance: 14.0 days
Overall length: 5.0 m
Maximum diameter: 2.4 m
Total mass: 5,682 kg
Propellant mass: 362 kg
RCS total impulse: not available
Primary engine thrust: 15.83 kN
Main engine propellants: nitrous oxide/amine
Total spacecraft delta v: 215 m/s
Power: batteries; 24.0 kW total

Reentry module

Crew size: 3
Diameter: 2.3 m (sphere)
Total mass: 2,900 kg
Attitude control: none
Environment: oxygen + nitrogen at 1 atm
Controls: as Vostok 3KA
Landing system: Sphere made ballistic reentry, with shield side seeking correct orientation by virtue of the center of gravity being aft of the center of the sphere.
Parachutes: single with suspended retrorocket package for soft landing. Crew stayed within the capsule.

Equipment module

Length: 2.3 m
Maximum diameter: 2.4 m
Total mass: 2,300 kg
Propellant mass: 275 kg
Reaction control system
- thrusters: not available
- propellant: cold gas (nitrogen)
- specific impulse: not available
- total impulse: not available
Retro-rockets
- thrust: 15.83 kN
- propellant: nitrous oxide/amine
- specific impulse: 266 s
- delta v: 155 m/s
Power: batteries; 24.0 kW total, 0.20 kW average

Auxiliary retrorocket module

Length: 0.6 m Maximum diameter: 0.3 m Total mass: 143 kg Propellant mass: 87 kg Thrust: 117.7 kN Propellant: solid Specific impulse: 224 s Delta v: 60 m/s

Voskod 3KD (1965)

This version flew twice, on 22 February 1965 unmanned (as Cosmos 57) and on 18 March 1965 manned as the Voskhod 2 spacecraft.

Reentry Module

Reentry Module: Voskhod SA. Also known as: Spuskaemiy apparat - Sharik (sphere).

Crew Size: 2
Length: 2.3 m
Diameter: 2.3 m
Mass: 2,900 kg
Heat Shield Mass: 837 kg
Recovery equipment: 151 kg
Parachute deploys at 2.5 km altitude
Crew lands in spacecraft. Touchdown rocket softens landing.
Ballistic reentry acceleration: 8 g (78 m/s²)

Equipment Module

Equipment Module: Voskhod PA. Also known as: Priborniy otsek.

Length: 2.25 m
Diameter: 2.43 m
Mass: 2,300 kg
Equipment in pressurized compartment
RCS Propellants: Cold gas (nitrogen)
RCS Propellants: 20 kg
Main Engine (TDU): 397 kg
Main Engine Thrust: 15.83 kN
Main Engine Propellants: Nitrous oxide/amine
Main Engine Propellant Mass: 275 kg
Main Engine Isp: 266 s (2.61 kN·s/kg)
Main Engine Burn Time: 1 minute (typical retro burn = 42 seconds)
Spacecraft delta v: 155 m/s
Electrical System: Batteries
Electric System: 0.20 average kW
Electric System: 24.0 kW h

Auxiliary Retrorocket Module

Auxiliary Retrorocket Module: Voskhod KDU. Also known as: Engine unit

Length: 0.60 m
Diameter: 0.25 m
Mass: 143 kg
Engine Thrust: 118 kN
Engine Propellants: Solid
Propellant Mass: 87 kg
Engine Isp: 224 s (2.20 kN·s/kg)
Spacecraft delta v: 60 m/s

General data

Total Mass:5,682 kg
Total Length: 5.0 m
Endurance: Supplies for 14 days in orbit
Launch Vehicle: Voskhod 11A57
Typical orbit: 163 km x 591 km, 64.8 inclinaton