EVAs in May

[GordonD]

26 MAY

 

1973 Paul Weitz [SEVA] (Skylab 2 CSM)

 

Duration 35 min

 

The Skylab Orbital Workshop had suffered major problems during its launch phase: the meteoroid shield had been ripped away by air pressure and telemetry indicated that the solar panels had not opened properly. Launch of the first expedition was delayed by nearly two weeks until a repair plan could be drawn up, When the CSM completed rendezvous, the astronauts reported that one solar panel was completely missing and the other was jammed in a partly-open position, a metal strap holding it in place. Weitz carried out a Stand-up EVA through the Command Module hatch and assembled a 4.5m pole with a hook on the end and attempted to pull the array open but without success. Pete Conrad had to use the attitude thrusters to stop the CSM being drawn towards Skylab. Weitz replaced the hook with a universal prying tool but this did not work either. The repair attempt was abandoned and the spacecraft docked with the Workshop while Mission Control considered what to do.

 

First EVA for Weitz.

[GordonD]

27 MAY

 

2011 Michael Fincke & Greg Chamitoff (STS-134/ISS)

 

Duration 7 hr 24 min

 

The astronauts permanently transferred the Orbiter Inspection Boom to the ISS. This device had been carried in the cargo bay on previous flights and was used to extend the reach of the station's manipulator arm; however with the Shuttle era drawing to a close it would be left behind when Endeavour departed for home for the last time. A Power Data and Grapple Fixture was attached to the boom so that the station's arm could grasp it at one end rather than in the middle as before, extending its reach even further. Finally the astronauts installed a spare arm on the Dextre robot.

 

This was the last EVA carried out by a Shuttle crew: one would take place while STS-135 was docked to the ISS but it would be conducted by station residents. It was the ninth and last for Fincke, giving a career total of 48 hr 37 min; the second and last for Chamitoff: his total is 13 hr 43 min.

[GordonD]

28 MAY

 

1986 Leonid Kizim & Vladimir Solovyov (Salyut 7 Expedition 6)

 

Duration 3 hr 50 min

 

Kizim and Solovyov had arrived on Salyut three weeks earlier - not directly from Earth but from the new space station Mir. The previous Salyut expedition had been terminated early due to crew illness and several tasks had been left incomplete. After spending 52 days on Mir, the cosmonauts had performed the first transfer between two space stations in order to tie up all the loose ends. These included two EVAs, the first of which involved recovery of space exposure experiments (studying the effects on power and data cables, threaded connectors on nuts and bolts, metals and biopolymers) and a Soviet-French micrometeoroid collector. They then attacked a space assembly device outside the airlock hatch, which could deploy a 15m tubular metal truss. Unlike the systems tested on the US Shuttle, which were pieced together like a construction set, this device was operated by hinges and springs. By adding more folded units the length of the truss could be increased to a kilometre or more, according to the designers. Kizim extended the truss and climbed halfway along it, finding it sturdy and stable. The far end carried a device to assess the environment around the station,. As the EVA drew to a close, the cosmonauts fitted a visible light communications system on a station porthole, then retracted the truss.

 

Seventh EVA for each cosmonaut.

 

 

1995 Vladimir Dezhurov & Gennadi Strekalov [IVA] (Mir Expedition 18)

 

Duration 21 min

 

This was an Intra-Vehicular Activity, in which the cosmonauts were in space-suits in full vacuum but remained within Mir at all times. They entered the transfer compartment (the spherical module at one end of the Mir complex, to which the four radial modules would ultimately be attached) and sealed it off, then depressurised it. They then removed the docking drogue from the -Y port and replaced it with a hinged flat plate door, opened an identical door on the -Z port and fitted the drogue there.

 

Fourth EVA for Dezhurov; fifth for Strekalov

 

 

 

Intra-Vehicular Activity? To quote myself from a previous post: 

 

The Americans and Russians have different definitions on what constitutes an EVA. For the Americans, an astronaut must have at least his head outside the spacecraft to qualify: for instance, when the J-series Apollo flights were returning from the Moon, the CMP would carry out an EVA to retrieve the film cassettes from the Service Module's SIMBAY, while the LMP assisted. Because the LMP had his head and upper torso out of the Command Module hatch, he was credited with a Stand-up EVA (or SEVA), while the mission Commander was not, even though he was suited up and in vacuum, because he remained inside the spacecraft at all times.

 

In contrast the Russians class an EVA as any time a cosmonaut is in vacuum in a space-suit, even if they do not venture outside the spacecraft: for example, after the Progress M-34 freighter collided with Mir in 1997, Anatoli Solovyov and Pavel Vinogradov carried out an inspection of the damaged Spektr module from the inside. This was classed as an Intra-Vehicular Activity or IVA. 

 

The reason for this is because the Russians have always used an airlock of some sort, meaning that cosmonauts not actively involved in the EVA remained under normal pressure, whereas on Gemini and Apollo missions the entire spacecraft was depressurised, but it was still felt desirable that a distinction be made between those performing the EVA and those not taking part.

[GordonD]

29 MAY

 

2019 Oleg Kononenko & Alexei Ovchinin (ISS Expedition 59)

 

Duration 6 hr 1 min

 

The cosmonauts installed a new handrail on the Russian segment of the station, retrieved science experiments from the Poisk Module, jettisoned the plasma wave experiment hardware, and carried out routine maintenance work, including cleaning the window in the Poisk hatch.

 

Fifth and last (to date) EVA for Kononenko: his career total is 32 hr 13 min. Ovchinin's only EVA to date. Both cosmonauts are still on active flight status so this could change in the future.

[GordonD]

30 MAY

 

1996 Yuri Onufrienko & Yuri Usachyov (Mir Expedition 21)

 

Duration 4 hr 20 min

 

The cosmonauts installed the US-built Modular Optoelectrical Multispectral Scanner (MOMS), which had been launched inside the Prirora Module and had already been flown on two Shuttle missions. The EVA was observed, with some difficulty due to Mir's small viewports, by the third crewmember, US astronaut Shannon Lucid. Before it began, Onufrienko had placed a piece of red tape across controls that she was not allowed to touch!

 

Fourth EVA for both cosmonauts

 

 

1999 Tamara Jernigan & Daniel Barry (STS-96)

 

Duration 7 hr 55 min

 

This was the second Shuttle mission to dock with the as-yet-unoccupied ISS, which at this stage consisted of only the Zarya baseblock and the US Unity Module. Now, the astronauts added two cargo cranes: the Russian Strela and the American ORU Transfer Device, which would be used to manipulate large components during the assembly flights to come. They also attached three bags of EVA tools and installed foot restraints (designed to fit the boots of both US and Russian suits) and handrails. They then fitted an insulation cover over Unity's trunnion pin and examined one of its antennas, then photographed the exterior of the Shuttle orbiter.

 

Technically the first and only EVA for Jernigan, though on a previous flight she had been scheduled to perform one but this had to be cancelled because the outer airlock hatch could not be opened. Counting this as an IVA, her total career time amounts to 9 hr 47 min. Second EVA for Barry.

 

 

2007 Fyodor Yurchikhin & Oleg Kotov (ISS Expedition 15)

 

Duration 5 hr 25 min

 

The prime objective of this EVA was to fit the Zvezda Module with panels to protect it against orbital debris. The cosmonauts exited the station through the Pirs airlock and split up: Kotov moved to PMA-3 (the Pressurised Mating Adapter) and directed Yurchikhin, using the Strela 2 crane, to pick up a rack containing seventeen protection panels (known as the Christmas Tree) and transfer it, and himself, back to a grapple fixture on Zvezda. Yurchikhin then joined Kotov and they rerouted a cable before opening one bundle of panels, which they attached to the conical fairing between Zvezda's two sections.

 

First EVA for both cosmonauts.

[GordonD]

31 MAY

 

1986 Leonid Kizim & Vladimir Solovyov (Salyut 7 Expedition 6)

 

Duration 4 hr 40 min

 

The cosmonauts finished off the remaining tasks left incomplete when the previous Expedition had to be cut short due to crew illness. They extended the URS truss then used the device at the far end to measure its stability. The instruments included a small seismograph to track the minor vibrations in the station's structure when its attitude thrusters were fired. A camera was also used to film an orange beacon at the tip of the truss to measure different frequencies of vibration. The truss was retracted again and the cosmonauts fitted an instrument called Mikrodeformator, studying aluminium-magnesium alloy reactions to repeated structural loads. Finally they retrieved a sample of solar cell material left outside the previous August. This was the last EVA to be conducted from Salyut 7: the cosmonauts would remain aboard for a further four weeks before transferring back to Mir.

 

This was the eighth and last EVA that the two cosmonauts had conducted together: their career totals amounted to 31 hr 38 min each.