T-6 Down at Laughlin

[KingGuy]

Engine was shutdown by the IP due to rapid reduction to idle during a straight-ahead rejoin.

No way. Pulling the PCL from MAX into IDLE is a technique to drop overtake quickly on a rejoin (as in the IDLE position, the prop blades are pressurized to windmill perpendicular to flight path creating max resistance). If the engine shut off from moving the PCL from MAX to IDLE quickly, they wouldn't have blamed the pilot for the error - I slammed the power from MAX to IDLE and back sixty nine thousand times as a student who had trouble learning to anticipate power... and I'll bet I'm not the only one.

I also heard that the IP over flew several field that he was on profile for and that the student "saved the day" by "suggesting" that the crew eject at ~500' AGL vs. the mandatory 2000' AGL FL ejection.

I remember when the event happened looking at the area that they were rumored to be assigned to and if they were in a low area (as formations often request), I think it could have been tough to get to a usable field. They report says they missed that decision, so either I remember incorrectly, or they're hanging him out to dry a bit.

Improper application of ORM-321

Doesn't that only apply when you are on landing profile to a runway? I don't remember. Can anybody refresh my memory?

Could you link to the full report?

2

[HU&W]

Doesn't that only apply when you are on landing profile to a runway? I don't remember. Can anybody refresh my memory?

Sort of. It primarily refers to the ejection decision. If you don't have the criteria met at ejection altitude (including landing profile), it's time to go.

[sky_king]

I have no idea what happened in this case, but I'm sure its possible if you get the air/gas/fire combination out of sequence or out of balance.

I had to look this up but the boldface for an immediate air re-start is

PCL-OFF

STARTER SWITCH-AUTO/RESET

PCL-IDLE, ABOVE 13% N1

Somone else can post the exact warning but bad shit happens if you go immediately from OFF to IDLE.

2 on it being pretty hard to lift over the gate accidentally.

The problem is't going from OFF to IDLE right away. The engine won't spool down fast enough to get below 13% N1 by the time you get to the boldface, even if you are doing it slowly. The problem is going above IDLE before the engine has properly spooled up to 67% N1 (Flight Idle). During an airstart, the PMU does not manage the ITT, torque, etc. like it does on the ground. If the PCL is pushed up too early, fuel is introduced at a rate faster the the engine can burn it. This creates a very big heat flash melting and warping the blades in the engine. With the number of blades in the engine and the precision required for it to run, it doesn't take much to completely destroy the engine. I wouldn't be surprised to see a 4th step to the boldface in the next -1 change to wait until flight idle N1 before pushing the PCL past the IDLE position.

I also heard that the IP over flew several field that he was on profile for and that the student "saved the day" by "suggesting" that the crew eject at ~500' AGL vs. the mandatory 2000' AGL FL ejection.

The crew did not perform a Turn Climb Clean Check but they were never on profile for a suitable landing surface. The IP did a lot of things wrong, but by the point the irreversible damage was done, there was no place for him to put it down. Don't pin that on him too.

Oh very good point, didn't realize they were on a rejoin. I have no idea wtf he was doing then.

Never heard of it happening before. And if so, this would be much more prevalent with all the stud's panic stopping on rejoins. Hell, I can't even count how many times I would go idle/boards on a rejoin...probably every rejoin I did on my first handful of form flights. Multiply that by...all of UPT and if it was an issue with the PT6 then there would be T-6's falling out of the sky at a very rapid rate.

This is not a problem with the PT6. It is a problem with the design of the engine cutoff. Imagine an inexperience IP sitting in the back, arms on the rails, and he sees the student turn into lead with way too much closure. Depending on the range and closure rate, adrenaline starts to pump and he lurches forward to grab the PCL. If he overshoots by 1/2", he can easily hamfist the cutoff gate and rip the PCL back to OFF. This isn't an uncommon occurance. I've heard of several inadvertant shutdowns in the T-6 for this specific reason (at least 3 at Laughlin since I've been here). Most don't make the news because immediately pushing the PCL back to IDLE usually relights the engine. Supposedly there is a fix in the works to make the PCL cutoff a two-handed device but it's not going to come online for several more years. (unverified)

Edited March 5, 2011 by sky_king

[SurelySerious]

You can flame the T-6 out by a rapid reduction to idle?

As said above, shouldn't happen. Aside from everyone, myself included, having Empirical data on the matter, all power requests go through the PMU, a digital engine control. Being a computer, it has no feeling of fear that may arise from excessive closure, and it moderates between the user input and prevailing conditions pretty well.

[Karl Hungus]

Was he/she a FAIP? Just curious.

[C-21.Pilot]

Was he/she a FAIP? Just curious.

No. Prior KC-135. Not trying to point fingers, but the IP was a recent (i.e. a week or two prior to PCS) Aircraft Commander upgrade in the -135. When the AETC/CC safety crew (Col Elder) came here to Columbus to give the safety details, that was pointed out.

Regardless, the guy was a IP signed in the letter of X's...he was just as qualified as the next guy -- maybe, not as experienced though.

Don't read too much into it.

[contraildash]

I'm as interested to hear how you could damage the engine in a restart attempt to permanently disable it.

If you do a start/restart improperly on a turbine/jet you most certainly can exceed ops limits and trash the engine. Read the SIB for more.

[Toro]

Not trying to point fingers, but the IP was a recent (i.e. a week or two prior to PCS) Aircraft Commander upgrade in the -135. When the AETC/CC safety crew (Col Elder) came here to Columbus to give the safety details, that was pointed out.

Is A/C a requirement for tankers/heavies?

4-Ship flight lead is required for fighter guys to be IFF instructors, not sure what (if anything) is required for UPT.

[Ram]

For fighter guys, I think a 2FL qual is required for UPT instructors.

[sky_king]

There are UPT instructors that were never aircraft commanders in heavies.

[osulax05]

Imagine an inexperience IP sitting in the back, arms on the rails, and he sees the student turn into lead with way too much closure.

An inexperienced IP should not be sitting back with his arms on the rails during a rejoin, nor should any IP. One of the only things that will kill you in an instant at altitude is another jet. IPs should be extremely guarded during that phase of flight. If he was really doing that then it is a foul and it's not surprising he F'd up and shut the motor down in a panic.

/Disclaimer. This is just my observation. I'm not trying to make a point about this incident.

The only thing that came close to scaring me in the jet at UPT was flying formation with a certain IP. He thought formation was the time to get up there and have fun. He flew rejoins with way too much aspect and Vc and more often than not had to do a quarter plane to avoid a massive overshoot and thought he was flying BFM during ET Level III. He was the most mellow and cautious guy on any other sortie but when it came to formation he was a complete dip shit. The shit really hit the fan when he had to do a lag roll on the RTB to avoid a mid-air with the DO in the other a/c. I also noticed this in a few other pilots though not to this extreme.

I agree that formation flying is a blast. But in my limited time at UPT it seemed like some IPs had the wrong mindset about formation. Formation flying is a means to accomplish the mission. It is admin. It is not THE mission and it certainly isn't about shining your ass and trying to see who can be the most aggressive. Most of the IPs I flew formation with at UPT were a lot less aggressive with the airplane and low and behold were able to complete rejoins quickly and without attracting flight lead's attention. Isn't that the point?

Anybody else see stuff like this?

[Guest Crew Report]

There are UPT instructors that were never aircraft commanders in heavies.

That's pretty scary considering KC-135's upgrade in house (not at the FTU) and average time is 2-3 years at an assignment. I know plenty of AC's that went to UPT and weren't IP's in the -135. What's funny about that is AMC doesn't consider PIT to be a true MWS instructor course. So after they're teaching at a UPT base for 3-4 years and go back to the tanker, they have to then go to IP school.

[lj35driver]

It used to be by waiver only to go to a UPT assignment out of the heavy world without having been at least an AC. Everyone from my sqd recently asking for AETC assignments were required to have upgraded before even being considered. They were told that waivers were no longer accepted to take them as FPs.

[AZwildcat]

I think the consensus here is that if Laughlin had a "C'mon Man" TV segment...this would be number one.

[Techsan]

There are UPT instructors that were never aircraft commanders in heavies.

Yeah, they are called FAIPs.

I know in the KC-10 community, those that are sent to UPT assignments are all at least ACs. About 90% of KC-10 guys that go down to AETC are ACs, and 10% IPs. Of those percentages, I would say that about 75% of both ACs & IPs were very new to their qual.

We seem to do that quite often these days in our community, that is upgrade someone early so that they could qualify for a particular assignment. We recently had a guy get a G-V assignment (required IP) before having started IP upgrade. He must have had dirt on the CC.

[sky_king]

Yeah, they are called FAIPs.

It's not common. Also, I wasn't saying the IP in question had his hands on the rails, just to imagine it. Even guarding the controls constantly, I've seen studs do things that will make you pinch some seat cushion. When you are seconds away from hitting another aircraft, it doesn't matter where your hands are, you're going to jump a bit.

[Bronco130]

Not if the IP was a former -37 guy. They lost one at Randolf with two very experienced IP's on it for this reason.

T-37 flap lever = T-6 throttle cutoff

I could see that being a factor if the engine was shut off during the landing phases of flight.. but this was a rejoin so doubt the IP was lowering the flaps.

[Herk Driver]

Is A/C a requirement for tankers/heavies?

Yes, but it can be waived.

[Whitman]

Why would anyone PCS as a copilot to be an AETC IP? I've always heard nothing you do as a Copilot is good.

Edited March 5, 2011 by Whitman

[TarHeelPilot]

Why would anyone PCS as a copilot to be an AETC IP? I've always heard nothing you do as a Copilot is good.

It has happened, as mentioned above via waiver. Particularly if the losing unit really doesn't care about losing you.

[Skitzo]

I believe my prior community (Bones) sent guys regularly to AETC as copilots.

[Majestik Møøse]

There are UPT instructors that were never aircraft commanders in heavies.

Really? People leave as copliots to go back to UPT? That sucks. At least they can be the AC there...

[Hacker]

I believe my prior community (Bones) sent guys regularly to AETC as copilots.

Does that mostly have to do with the (lack of) flying time that most guys in the BONE are (were?) getting?

[POKESC17]

I believe my prior community (Bones) sent guys regularly to AETC as copilots.

C-17 copilots where getting picked off in C-17's around 2008

[nunya]

This is not a problem with the PT6. It is a problem with the design of the engine cutoff. Imagine an inexperience IP sitting in the back, arms on the rails, and he sees the student turn into lead with way too much closure. Depending on the range and closure rate, adrenaline starts to pump and he lurches forward to grab the PCL. If he overshoots by 1/2", he can easily hamfist the cutoff gate and rip the PCL back to OFF. This isn't an uncommon occurance. I've heard of several inadvertant shutdowns in the T-6 for this specific reason (at least 3 at Laughlin since I've been here). Most don't make the news because immediately pushing the PCL back to IDLE usually relights the engine. Supposedly there is a fix in the works to make the PCL cutoff a two-handed device but it's not going to come online for several more years. (unverified)

Whiting had an inadvertent T-6B shutdown a few months ago when the PIT stud moved the PCL abruptly to idle during an OCF (out of control flight) recovery drill and he had NOT raised the cutoff. One of the pins that was supposed to prevent the PCL from moving too far aft wasn't seated properly and let the PCL move past IDLE to OFF. They were able to reproduce the failure on the ground after the flight. Though their restart went better than this guy's, so nobody really heard about it. There's talk about a fix here, too, but no real progress that I've seen.