Entry Tutorial

After Columbia decided that several of its associates would benefit from an entry tutorial, intended for both use in the Orbiter Space Flight Simulator, and for understanding the Columbia STS-107 disaster.

Welcome After Columbia's Entry Tutorial. This tutorial uses the standard take off scenario from Orbiter (Checklists - Mission 1 - DG to ISS) with a few modifications:

- The main propellants have been offloaded to 35%, or 3990kg. This can be done by finding the PRPLEVEL parameter in your scenario file. It was done to ensure a minimum mass, a standard procedure of my own to reduce the loads on the ship and to reduce landing speed.

- The RCS propellants have been reduced to 30kg.

The reason I have done this entry tutorial is to teach people in the amateur/hobby aerospace field more about entry, and to help the curious understand the STS-107 disaster better. The effects on the Delta Glider as modelled in Orbiter are fundamentally similar to those that act on a Shuttle during reentry. Many have questions about Columbia.

If a Shuttle can only survive RCC holes smaller than one square inch, how did Columbia make it all the way to Texas with a 72 in2 hole?

Why is the Shuttle so hot when it hits the atmosphere?

Why was the debris field so large?

Why did the left wing pieces fall farthest west, while the main engine powerheads made it to Louisiana?

Why did some pieces hit the ground faster than a bullet and some fluttered like bird feathers?

What happened to the crew and what would have happened if Columbia lasted another minute or two?

Answers to these questions and the understanding behind being able to answer them is key to understanding the Columbia Accident Investigation Board's report and especially the technical Appendix documents. I invite any interested individuals and the media to refer to this tutorial whenever you desire to enhance your understanding of spacecraft descent and entry.

At the end of (and sometimes throughout) each page is a detailed procedure for piloting the Delta Glider in Orbiter. These are not definitive and require further testing, so you can't sue me for killing yourself in the simulator, but I will offer a full refund of my charge :). As I have yet to successfully deadstick land from entry interface to the runway without application of power...well, I'm sure you can figure the rest out.

Terry Wilson

aftercolumbia.tripod.com

Next: Deorbit and Coast

At the completion of orbital operations the Orbiter is oriented in a tail first attitude by the RCS and an OMS burn reduces the Orbiter's velocity 200-500 fps, depending upon orbital altitude, in preparation for deorbit.

The RCS turns the Orbiter's nose forward for reentry which occus at 400,000 feet, slightly over 5,000 miles from the landing site. The velocity at reentry is approximately 17,000 mph with a 40-degree alngle of attack.

The guidance system must dissipate the tremendous amount of energy the Orbiter possesses when it reenters the Earth's atmosphere to ensure the Orbiter does not either burn up (entry angle too steep) or skip back out of the atmosphere (entry angle too shallow).

Dennis R. Jenkins; Space Shuttle: The History of the National Space Transportation System, The First 100 Missions, 3rd Edition, Motorbooks International and Voyageur Press 1989-2002.

and no, they did not pay me to say that!

All cyan colored text throughout the tutorial (excuding headers and footers) is quoted from

Dennis R. Jenkins' Space Shuttle: The History of the National Space Transportation System, the First 100 Missions, Motorbooks International and others, 1989-2002, pp. 260-261.