Design
Progress is of much the same size and shape as Soyuz. It consists of three modules:
- A pressurized forward module. This carries the supplies for the crew such as scientific equipment, clothes, prepackaged and fresh food, and letters from home. The docking drogue is similar to that of the Soyuz but features ducting for the UDMH fuel and N2O4 oxidiser.
- A fuel compartment. The reentry module of the Soyuz was replaced with an unpressurized propellant and refueling compartment with ducting along the outside of the spacecraft. This meant that if a leak occurred, the poisonous gas would not enter the station's atmosphere. The fuel is carried in two tanks.
- A propulsion module. The propulsion module, at the rear of the spacecraft, remained unchanged and contains the orientation engines used for the automatic docking. It may be used to boost the orbit of the station once docked.
Reduction in mass was possible because the Progress was designed to be unmanned and disposable. This means that there is no need for bulky life support systems and heat shields. The spacecraft also has no ability to split into separate modules. After undocking, the spacecraft performs a retrofiring and burns up in the atmosphere.
Read more about this topic: Progress (spacecraft)
Famous quotes containing the word design:
“Joe ... you remember I said you wouldnt be cheated?... Nobody is really. Eventually all things work out. Theres a design in everything.”
—Sidney Buchman (19021975)
“With wonderful art he grinds into paint for his picture all his moods and experiences, so that all his forces may be brought to the encounter. Apparently writing without a particular design or responsibility, setting down his soliloquies from time to time, taking advantage of all his humors, when at length the hour comes to declare himself, he puts down in plain English, without quotation marks, what he, Thomas Carlyle, is ready to defend in the face of the world.”
—Henry David Thoreau (18171862)
“Humility is often only the putting on of a submissiveness by which men hope to bring other people to submit to them; it is a more calculated sort of pride, which debases itself with a design of being exalted; and though this vice transform itself into a thousand several shapes, yet the disguise is never more effectual nor more capable of deceiving the world than when concealed under a form of humility.”
—François, Duc De La Rochefoucauld (16131680)