Shuttle Engine Emergency

[vonjager]

Some slick work by NASA. What a scary moment.

[gromomotta]

What mission was this? Was that the only mission so far that had to abort into orbit?

[blablubb12345]

@gromomotta

STS 51F. It was the only in-flight abort in the shuttle program.

[doginstine]

There was talk about the first flight of the shuttle of testing a RTLS. John Young said "NO WAY!"

[RoPWU]

@doginstine

"NO WAY THIS SHUTTLE IS WORKING?'

or "NO WAY, IM STILL ALIVE"

[blablubb12345]

@RoPWU

I think he said someting like "let's no play russian roulette". An RTLS abort would be a very tricky and dangerous manouver.

[TechmanFred]

nope

It blew up later

[Boy75402]

SEVERAL launches later, dear.

[claydon82]

what does abort to orbit mean? they were trying to orbit anyways

[lolvks]

Abort to Orbit means that the shuttle orbits at a lower altitude than originally planned

[blablubb12345]

Abort to orbit means reaching a lower than planned, but safe orbit. Other abort modes are a transoceanic landing in Europe or a flyback to KSC, it all depeds on how fast the shuttle already is at the point of the engine loss. The lower orbit of this flight was sufficient to achieve their main mission goals.

[btardwannabe]

Abort to Orbit usually means that the shuttle goes into the orbit it can reach with whichever functioning engines it has. It will generally then go once around and re-enter and land.

[rdfox76]

@btardwannabe Actually, an ATO is intended to allow completion of the mission despite the problem. Abort Once Around is what they'd have had if they'd lost the second engine at the time they commanded the limits to inhibit, which is where they come back and land at Edwards the first time by.

[EMT308]

@rdfox76 Actually I think that and ATO is when the intended orbit altitude cannot be reached, but a safe, lower one can be. This may not totally cancel the mission, but it is not a "continue with planned mission" situation. The only time when the mission will go on as planned including reaching the desired orbit is after Press to MECO is reached. (Or single engine Press to MECO) Past that point, any "abort" is pretty much not needed since the shuttle will continue as planned.

[ncadkins]

Challenger's frame was actually older than Columbia's. If I remember my history right, it was built as a stress-test vehicle. However, when Enterprise's frame was not found spaceworthy, they decided to fit Challenger up as a flight-ready vehicle. At the time of it's final flight, it had flown more missions than any other shuttle, including at one point flying four times in three months.

[Ronsmytheiii]

@ncadkins Ov-101 did have a spaceworthy airframe, it just would have cost much more to convert her than the STA-099 with the design changes initiated after the construction of Columbia (ov-102)

[vicorly]

@ncadkins You're mostly right. Challenger started life as STA-099, and Columbia was Orbital Vehicle OV-102. (Enterprise OV-101, Discovery OV-103, Atlantis OV-104 and Endeavour OV-105).

The contracts to build Enterprise, Columbia and Challenger were awarded on 7/26/1972 (when I was 29 days old).

Enterprise began construction 6/4/1974, Columbia on 3/27/1975, Challenger (as STS-099) on 11/21/1975. Columbia's construction finished on 3/8/1979. Challenger's conversion into OV-099 began 1/28/1979.

[vicorly]

@ncadkins As for the exact reason of why they converted STA-099 into Challenger...

NASA planned to refit the prototype orbiter Enterprise (OV-101), used for flight testing, as the second operational orbiter. However, design changes made during construction of the first orbiter, Columbia (OV-102), would have required extensive rework. Because STA-099's qualification testing prevented damage, NASA found that rebuilding STA-099 as OV-099 would be less expensive than refitting Enterprise.

[crazybastard82]

at least it wasn't an RTLS abort....one of those would be terrifying: flipping yourself backwards, firing the engines, waiting several minutes for the engines to cancel downrange velocity, then falling like a brick until the engines have enough time (and thrust, since you've lost one or two) to build up enough speed to get you all the way back to florida....good luck in that situation. i believe sts-51 was the only inflight abort?

[UdallIn72]

That's right.

They've had six aborts on the pad after main engine start, though.

...It's too bad they've really never gotten this thing past the prototype phase.

[chellysell]

This footage is from the STS-51F mission using the shuttle Challenger on her 8th mission. This is when the center main engine shuts down 5 minutes and 45 seconds after liftoff. I like when CAPCOM says, "Challenger, Houston. Abort ATO."

[thenekom]

I'm just amazed how QUICKLY they said that. Those guys train for it, and they were ready for it.

[dmullerdotnet]

You are right thenekom. It was a sensor problem, and loosing another engine shortly after center engine out would have meant ditching in the sea as neither RTLS nor Zaragoza would have been achievable. Another engine was about to shutdown due to same sensor problem (at 3:42 in the clip), so they overrode the sensors with command "limits to inhibit".

[dmullerdotnet]

well change "ditch in the sea" to highly risky "bailing out of the shuttle". This was very close to a disaster.

[tomdg65]

This was prior to the Challenger accident. No bailout capability existed for the crew at that time.

[dvnrrs]

If loss of a 2nd engine meant certain loss of crew, wouldn't the computer be smart enough to know it can't shut down additional engines for any reason? Who cares if the fuel turbine temp is high... if you NEED those remaining 2 engines to survive, keep 'em burning! Better to ignore the fault indications and keep burning and have a _chance_ of survival than to just shut the 2nd engine down and have NO chance of survival.

[dvnrrs]

(And I guess this is exactly what the flight controller decided to do... I'm just surprised it took a "quick thinking flight controller" to make that decision, when that logic could easily have been programmed into the computers.)

[UdallIn72]

A crash landing's still a better option than an engine explosion.

[Cellmate412162]

@dmullerdotnet Correction. If that other engine shutted down, Challenger would have went into an Abort Once Around since the orbiter was past TAL, as it was mentioned between 3:42 & 3:45.

[emenentia]

Actually.. im thinking the wrong thing. I am thinking RTLS....

[emenentia]

OK so how exactly does the ATO procedure work?

[littlepyro]

Dump extra fuel for that Engine and continue to space, basically.

RTLS on the other hand.... ;)

[columbusmozart]

ATO pushes the orbiter to a lower orbit to allow it to return to the launch base. RTLS is essentially to get it above the atmosphere, turn it around and deorbit backwards back to the launch base. RTLS is very risky due to the excessive G-loads in the nulling of the forward velocity. The sims give it about a 10% success.

[Membrane556]

It turned out being a defective sensor vs an actual engine failure.

The shuttle also is one of the few vehicles that can handle an engine failure in flight.

The other three were the Saturn Rockets and Falcon 9

[Yevv]

Pilot is the coolness it self!

[joachim2464]

The engines on the space shuttle is pretty reliable considering the number of flights

[thenekom]

It wasn't even an engine failure if I remember right, it was a failed sensor that shut it down. I believe I heard when they called out "limits to enable" that told them to override similar sensors on the other 2 so they wouldn't suffer the same failure. But I could be wrong.

[Superedit]

Whew - some serious "puckering" in the "Trench", where the FIDO and BOOSTER controllers sit. Nothing like earning a year's pay in five minutes...nice job by all hands.

[varde144]

what is the STS numer on this launch

'

[dullguy]

51-F/STS-26

[da40flyer]

This wasn't STS-26. 26 was the first return to flight after Challenger, flown by Discovery.

[jlart1]

The mission depicted here was STS-51-F.

[KevinKGB474]

51-F is the right mission assignment, before the return to flight STS-26, NASA went by the flight designation of 51-F. the first number was the fisical year the flight was scheduled (ie 1985) the 1 launch point (ie KSC) and F was the letter for the number of flight it was scheduled during said fisical year. 51-L (Jan. 28, 1986) it was scheduled to fly in fisical year 1985 but due to delays, was pushed back to early 1986

[ancestron]

Sometimes I think they shouldn't have named her Challenger, maybe that's part of the reason she was pushed. But soon after thinking that, I realize that was actually the perfect name for her.

[falconlem]

Good posting, I remember watching this launch in middle school. Of course this video is nowhere near as clear, but something is better than nothing. Anyone seen the once where the giant icicle of urine is hanging on the shuttle!@ been a long time sense I've seen that one.

[BigBill783]

The NASA Public Affairs Officer commentating in Mission Control, Houston on this flight here is Brian Welch.

[BigBill783]

No one is actually 'flying' the shuttle during the launch/ascent phase--its all done by computers.

[wuzzlevideos]

It can of course be taken over manually, just in case.

[jupitorman]

i remember when it happend the shuttles master alarms sounded as the engine started to have problems the pilot flying the shuttle noticed decresse in power then the engine shut down

[BigBill783]

Mission STS-51F Challenger

[NJCAT22]

Followed the shuttle for years and never knew this... Thanks...

[Jumpa31]

The fuel turbine temp failed. Houston ordered the crew to inhibit Main Engine limits. The crew does this to ensure the shuttles computers dont auto-shutdown any other engines due to it sensing exceeding any programmed limits. The normal engine running time is about 8:30. With only two engines running, the fuel would last longer so the crew dumped fuel to ensure a 9:41 burn. Keep in mind the engines run at 104% of rated capacity. I wasnt aware of this incident.

[BigBill783]

If a second engine had failed as it almost did--they wouldve done a TAL-transatlantic landing, landing in zaragoza, spain--it wouldve limped to Spain--or tried to anyway

[ClarkF1]

july 1985. The shuttle was Challenger. The engine shut down due to a faulty temp sensor. The same also happened with a second engine but a flight controller spotted this and stopped it happening. Had this happened NASA would have had problem because the shuttle wouldn't have had enough power to cross the Atlantic and they didn't have a crew bail-out procedure until after the Challenger tragedy

[jc851]

That is an excellent point, this was almost a (first) challenger disaster.

[chanjcw]

when did this happen?

[don312000]

Summer of 1985. Was actually the second engine problem on this mission...an earlier launch attempt ended with an on-the-pad engine shutdown at about 3 seconds before liftoff.