From: NASA HQ
Posted: Monday, October 27, 2003
What will the Soyuz TMA-2/6S crew (Expedition 7 + Pedro Duque) encounter during reentry/descent?
On descent day (10/27):
Special attention will be paid to the need for careful donning of the medical belt with sensors and securing tight contact between sensors and body.
During preparation for descent, before atmosphere reentry, the crew should settle down comfortably in the seat, fasten the belts, securing tight contact between body and the seat liner in he couch.
Dust particles starting to sink in the Descent Module cabin is the first indication of atmosphere reentry and beginning of G-load effect. From that time on, special attention is required as the loads increase rapidly.
Under G-load effect during atmosphere reentry the crew can expect the following sensations: Sensation of G-load pressure on the body, "burden in the body", labored breathing and speech. These are normal sensations, and the advice is to "take them coolly". In case of the feeling of a "lump in the throat", this is no cause to "be nervous". This is frequent and should not be fought. Best is to "try not to swallow and talk at this moment". Crew should check vision and, if any disturbances occur, create additional tension of abdominal pressure and leg muscles (strain abdomen by pulling in), in addition to the "Kentavr" anti-G suit .
During deployment of drogue and prime parachutes the impact accelerations will be perceived as a "strong snatch". No reason to become concerned about this but one should be prepared that during the parachutes deployment and change of prime parachute to symmetrical suspension swinging and spinning motion of the Descent Module occurs, which involves vestibular (middle ear) irritations.
It is important to tighten restrain system to fasten pelvis and pectoral arch. Vestibular irritation can occur in the form of different referred sensations such as vertigo, hyperhidrosis, postural illusions, general discomfort and nausea. To prevent vestibular irritation the crew should "limit head movement and eyes movement", as well as fix their sight on motionless objects.
Just before the landing (softened by six small rocket engines behind the heat shield): Crew should be prepared for the vehicle impact with the ground, with their bodies fixed along the surface of the seat liner in advance. "Special attention should be paid to arm fixation to avoid the elbow and hand squat".
Crew should not get up quickly from their seats to leave the Descent Module. They are advised to stay in the couch for several minutes and only then stand up. In doing that, they should limit head and eyes movement and avoid excessive motions, proceeding slowly. They and their body should not take up earth gravity in the upright position too quickly.
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