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Author
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Topic: Are all shuttle landings under manual control?
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Flying Dutchman
Member Posts: 161
From: Heemstede
Registered: Jan 2007
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posted 06-27-2007 02:38 PM
   
Is it so that during ALL the landings of the shuttle, the commander always landed the thing by hand, or has there been automatic efforts to land the shuttle? Or... has any pilot landed the craft? Just curious. |
Robert Pearlman
Editor Posts: 42988
From: Houston, TX
Registered: Nov 1999
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posted 06-27-2007 02:55 PM
All shuttle landings from STS-1 through STS-117 have been brought to a touchdown with the commander at its controls. That said, during the approach, its common for commanders to give their pilots a chance at flying, as it is good practice for when they become commanders and will be expected to land the orbiter. |
Max Q
Member Posts: 399
From: Whyalla South Australia
Registered: Mar 2007
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posted 07-04-2007 06:35 AM
Can the shuttle land automatically? |
Robert Pearlman
Editor Posts: 42988
From: Houston, TX
Registered: Nov 1999
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posted 07-04-2007 10:30 AM
Until very recently, the answer would have been no: a flight crew was required to start the APUs, deploy the landing gear, drag chute, and air data probe.As part of the post-Columbia provisions, specifically the procedures for "safe haven" (CSCS), wherein a damaged shuttle would leave its crew on the ISS and if deemed by the ground safe to do so, reenter and land under remote control (or be ditched in the ocean), a 28-foot cable was developed and now flies on the orbiter that connects the flight deck controls with an avionics bay in the middeck. |
Max Q
Member Posts: 399
From: Whyalla South Australia
Registered: Mar 2007
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posted 07-05-2007 05:02 AM
Now that seems odd as the Russian Shuttle the Buran was capable of a auto landing back in 1988 I would have thought the NASA vehicle would have been capable. |
Danno
Member Posts: 572
From: Ridgecrest, CA - USA
Registered: Jun 2000
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posted 07-05-2007 10:22 AM
It was the astronauts that made sure it was not autonomous. |
tegwilym
Member Posts: 2331
From: Sturgeon Bay, WI
Registered: Jan 2000
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posted 07-05-2007 10:45 AM
...but if you were a pilot, who would pass up a chance for some shuttle "stick time" in your logbook? Not me! |
GACspaceguy
Member Posts: 2475
From: Guyton, GA
Registered: Jan 2006
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posted 07-05-2007 11:58 AM
When it comes to the final approach I would want the human computer doing the landing. The subtle changes in winds and energy are better controlled by a real person. Also there is that old joke about the time when the computer was asked the same question "do not worry, nothing can go wrong — go wrong, go wrong, go wrong, go wrong." |
Max Q
Member Posts: 399
From: Whyalla South Australia
Registered: Mar 2007
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posted 07-06-2007 08:27 AM
quote:
Originally posted by GACspaceguy:
When it comes to the final approach I would want the human computer doing the landing.
An excellent point. |
kr4mula
Member Posts: 642
From: Cinci, OH
Registered: Mar 2006
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posted 07-06-2007 10:36 AM
We seem to have two different interpretations fo the question here. The original query was asking about an automated landing, i.e. completely under computer control. Robert's reply mentions the new equipment enabling "remote control," not automatic control. I'm assuming that means an astronaut on the ground would fly it like a UAV/drone and therefore it would still be landing under (remote) human control. Robert - is that your reading of the upgrade? I'm curious if they are building some sort of ground station for this. The remote option would seem more difficult/costly than providing an autonomous box to take advantage of the capabilities the shuttle already has and just fill in the gaps.Do those of you who feel the shuttle should be landed by a pilot, not a computer, feel more comfortable with that option? As I said in a similar thread on this topic a while back, the shuttle engineers felt there were no technical obstacles back in the 1970s to having fully automated landings, so I would have no reservations trusting some sort of 2000s computer to handle the landing now, especially in an abandoned shuttle. |
lewarren
Member Posts: 269
From: Houston, TX, USA
Registered: Aug 2001
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posted 07-06-2007 10:43 AM
If automated landings are so simple, why on Earth do we bother hiring airline pilots? |
Robert Pearlman
Editor Posts: 42988
From: Houston, TX
Registered: Nov 1999
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posted 07-06-2007 10:58 AM
quote:
Originally posted by kr4mula:
I'm assuming that means an astronaut on the ground would fly it like a UAV/drone and therefore it would still be landing under (remote) human control.
Not quite: without any modifications or cables added, it is my understanding the shuttle's computers can autonomously fly the orbiter to a landing. What the computers cannot do is start themselves, or deploy the landing gear, data probe or drag chute. These are irreversible actions and were they accidentally triggered at any other time then when nominally deployed it could threaten the safety of the crew. Thus these procedures were restricted to manual control only. The new cable allows for an empty shuttle (and thus no crew to risk) to land by allowing mission control to trigger these actions at the proper time from the ground. I tend to doubt it would need an astronaut on the ground to control or a separate ground station, as it is simply timed procedures. |
GACspaceguy
Member Posts: 2475
From: Guyton, GA
Registered: Jan 2006
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posted 07-06-2007 10:59 AM
I wonder if the computer would know to land long because of that alligator that just decided to sun itself, at the typical touchdown point on the runway, a minute before the touchdown? There are real time decisions that humans are better at making (like landing outside of the approaching boulder field). Don't get me wrong, if there are no living beings on board, then my all means let the computer fly it. At that point the criteria changes, the vehicle no longer needs to be man-rated. |
Robert Pearlman
Editor Posts: 42988
From: Houston, TX
Registered: Nov 1999
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posted 07-06-2007 04:26 PM
An alligator in California? Not likely. If a damaged empty shuttle is going to brought down for a landing, it's going to be directed to a site where there's the least chance of it flying over populated areas. I believe the current preferred site is Vandenberg AFB. |
John Youskauskas
Member Posts: 126
From:
Registered: Jan 2004
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posted 07-06-2007 05:06 PM
quote:
Originally posted by lewarren:
If automated landings are so simple, why on Earth do we bother hiring airline pilots?
Another old joke: Q: What is an airline CEO's idea of the ideal flight crew? A: One pilot and one dog... the pilot is there to feed the dog. The dog is there to bite the hand of the pilot if he tries to touch anything! |
spgrissom
Member Posts: 119
From: Mitchell, Indiana, USA
Registered: Apr 2003
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posted 07-06-2007 07:47 PM
When I was at Vanderberg AFB (12 years ago) the shuttle could have landed there. They had the launching abilities but that changed shortly before I seperated. VAFB is a great landing site. I understand why it was chosen and there would be little chance of hitting a populated area. Lompoc or Santa Maria in a drastic mistake but a slim chance. Even a slim chance of hitting main base. The FLT line is kinda out there a ways. |
OV-105
Member Posts: 816
From: Ridgecrest, CA
Registered: Sep 2000
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posted 07-06-2007 11:14 PM
I want to say in late 1987 or in 1988 NASA looked into flying Columbia on the STS-28 mission unmanned. They were going to do this because there was a shortage of the SRB fule for the Shuttle and Titan's. They were going to fly Columbia with a set of the old SRB's. I never hear on how far they got it on the project. |
GACspaceguy
Member Posts: 2475
From: Guyton, GA
Registered: Jan 2006
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posted 07-07-2007 08:16 AM
Robert, I must not have been clear in my alligator scenario. In the scenario, there is a crew on board and it is a typical KSC landing and not an emergency situation, so let me try again. It is a typical sunny Florida day. The Orbiter has just entered into the alignment circle and is moments away from landing. At the edge of the runway sits the alligator, it wasn't there when the KSC folks made their sweep but it has wandered to the edge of the runway (it didn't get the NASA brief on the landing that day). By now the orbiter has come out of the alignment circle and is on final. The alligator decides that the middle of the runway right there on those dark spots (the spots that are darkened from the touchdown rubber, left not by the Orbiters, but by the STA during their training flights), so out it goes. The Commander, having the best vantage point, all be it changing at rapid rate, sees the black 8ft streak head across the runway and reports in. The ground crew has now seen it and quickly confirms an alligator has come to rest right where the L/H MLG should be touching down. The Commander confirms and takes action to intentionally land long and communicates that he may require a max energy stop by using full braking so that the ground crew will be ready if there is an issue with the brakes and tires that may require immediate assistance. The commander floats the Orbiter over top of the alligator, which then takes off back into the underbrush, lands slightly long with no issues, crisis averted. In this scenario I don't want the computer flying. I don't want it to go like this; the commander sees the alligator, confirms the issue and then goes about taking control, feeling the spacecraft and taking action. I want the commander to have the feel of the vehicle, know where the vehicle is on energy because she/he has been flying it for some minutes up to that point and is one with the vehicle. I don't want the computer flying final if the commander can. What is the advantage? The human computer can process data faster, make rational decisions and respond quicker. There is no need to take such a valuable resource out of the loop just because the machine is capable of making the landing. This is not the same a flying an aircraft where most accidents are pilot error. In the case of the Shuttle system the Commander has significantly more training hours, there are no other vehicles in the pattern, weather and ATC issues are not part of the loop. By the way, in the alligator scenario above, it was not an orbiter and an alligator. It was a Gulfstream II, a deer and the aircraft came to rest off the runway, at the edge of a taxiway with the R/H tires flat because the heat fuses had blown. The pilot in command did a great job of keeping the aircraft on concrete, saving many hours of extraction from the soft soil at the end of the runway as well as the damage, an off runway event would have caused. The aircraft flew the next day, and our team was happy there was a human flying that day. |
Max Q
Member Posts: 399
From: Whyalla South Australia
Registered: Mar 2007
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posted 07-07-2007 09:56 PM
Again another compelling point but I am surprised that the actual landing system has never been commissioned for real. Another question arises now was it used in any of the pre-space landing tests before it was actually launched? |
taneal1
Member Posts: 230
From: Orlando, FL
Registered: Feb 2004
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posted 07-09-2007 06:47 PM
If memory serves, the initial plan was that the shuttle would be certified for a hands-off automatic landing ASAP. To that end, STS-3 was flown utilizing the Auto-Land system down to an altitude of 200 feet. At this point Lousma took over manually. He found himself over-controlling the shuttle during the landing flare resulting in a fairly hard landing. The astronauts opinion was that in the event of a failure of the Autoland system just prior to touchdown, it would be extremely difficult to take over manually and complete a successful landing. Subsequent flights have had the CDR take over just prior to intercepting the HAC. This allows him to get a "feel" of the shuttle's controls prior to landing. Further along in the shuttle program, management was concerned that during the long-duration missions, the CDR could have trouble re-adapting to gravity. Also, it was feared that following several weeks without practice landings the CDR would find it difficult to achieve a successful landing. Dave Walker trained extensively to demonstrate the Autoland capability but this objective was dropped shortly prior to launch. Walker was happier performing the landing himself, so he didn't mind at all... |
OV-105
Member Posts: 816
From: Ridgecrest, CA
Registered: Sep 2000
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posted 07-19-2007 02:04 PM
Which flight was it that Walker was going to have the auto land? I also want to say there was going to be an autoland test in 1984 with STS 41-F maybe I just remeber them saying in summer of 1984 and it was before the STS 41-D RSLS abort in June. |
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