TBM-700 Down in MA - N111RF

Sure looks like a high-speed near vertical arrival, not too long after takeoff. First WAG is a LOC. RIP.
 
Rick A said:
Sure looks like a high-speed near vertical arrival, not too long after takeoff. First WAG is a LOC. RIP.
Click to expand...

Looking at the ADS-B track and the reported weather, it looks like something happened before they hit the clouds causing them to descend back down to stay out of them. Then either the engine quit or they weren't paying attention to their speed and it stalled/spun.
 
I've been to that airport a few times and have driven that highway more times than I care to admit. Terrible, absolutely terrible weather to be flying in today. Here on Cape we've got several large trees down. The whole southern side of this area is experiencing near-storm conditions. Looks like they either never made the cloud layer or had just entered the layer when something went very wrong. Wind is from the east so the ground speed indicated being over 150 after turning south west makes for a very slow IAS. Wouldn't think it to be low enough to stall but the track certainly indicates the possibility of an engine failure.

Edit: Also, the initial turn should have been to the north west toward Providence based on the filed plan. Another impossible turn attempt? Going toward that stretch of I-195 makes sense...nice and wide and straight. But he would've been fighting a terrible crosswind to a tailwind.
 
This is on an IFR flight plan but not able to find the atc recording which I’m sure exists
 
This was a 2003 model, so a TBM 700 (not the 850 or 9x0 models that are also technically "TBM 700"s according to the type certification). No envelope protection unless they'd added a GFC600 somewhere along the way.

It was also sold very recently, so it's highly likely that the pilot had very little time in type.

I looked up the flight track, and they were WAY slow for the entire flight. I don't have it up any more, but they were at something like 90 knots if you subtract out the surface winds. That's rotation speed! (FWIW, Vy=123 KIAS and Vg = 110 KIAS on the 700.)

Also, after they leveled off around 500 feet, they did not accelerate. I don't think it's even possible to be at climb power level and hold that slow of a speed with full flaps and gear down, so they must have pulled or lost power at some point.
 
flyingcheesehead said:
This was a 2003 model, so a TBM 700 (not the 850 or 9x0 models that are also technically "TBM 700"s according to the type certification). No envelope protection unless they'd added a GFC600 somewhere along the way.

It was also sold very recently, so it's highly likely that the pilot had very little time in type.

I looked up the flight track, and they were WAY slow for the entire flight. I don't have it up any more, but they were at something like 90 knots if you subtract out the surface winds. That's rotation speed! (FWIW, Vy=123 KIAS and Vg = 110 KIAS on the 700.)

Also, after they leveled off around 500 feet, they did not accelerate. I don't think it's even possible to be at climb power level and hold that slow of a speed with full flaps and gear down, so they must have pulled or lost power at some point.
Click to expand...
Word on the street around here (3rd hand from someone that knows someone that works at EWB) is he was reporting engine issues. Whether that's fact or fiction IDK. Lots of rain around here the previous couple of days may have gotten some water in the fuel tanks...
 
Kitch said:
Word on the street around here (3rd hand from someone that knows someone that works at EWB) is he was reporting engine issues. Whether that's fact or fiction IDK. Lots of rain around here the previous couple of days may have gotten some water in the fuel tanks...
Click to expand...
Interesting. However, almost all "engine issues" are self-inflicted when it comes to a PT-6.

Also, I don't think water in the tanks is much of an issue on turbines. Jet-A is somewhat hygroscopic so some of the water will be absorbed, the Jet-A+ (with Prist) that the TBM requires will absorb even more. If there's any left, it would have to be a LOT to completely flame out the engine... And they must have had at least partial power to keep level and on speed the way they did for a bit prior to the crash. Water in a PT-6 is likely very close to an all-or-nothing scenario - Either the engine is gonna quit, or it's not.

There is a failure mode with the fuel control unit that can cause a partial power scenario like this, and there's a "MAN OVRD" (manual override) lever right next to the throttle lever that should be advanced in that case. Again, possibly due to low time in type the pilot didn't recognize it and/or didn't remember to use it. If you follow the checklists, that lever should be moved and locked during preflight, and check that it's locked immediately prior to start. After doing that enough times it should be second nature, and that's definitely something that we did in the sim.

I'll be very curious to see where this pilot got trained for the TBM, and how much time in type he had.
 
The preliminary report is out. It states that the pilot reported he was returning back to the airport (but report does not give any indication of the reason for the return). Pilot acknowledged instruction from tower to enter a left downwind for Runway 5 for the return, and when tower queried whether the pilot needed assistance on landing, the pilot said he did not need assistance. Next, tower asked whether the pilot needed an approach or radar vectors since the ceilings were ~1,000. Pilot said he would descend and that he "should be okay. Tower cleared him to land, and about a minute later tower gave the pilot a low altitude alert and altimeter setting. Pilot acknowledged the altimeter, but shortly after there was an intelligible exclamation from the pilot and no further communication. Report also notes that the cabin door, although it was in the open position when investigators arrived, was previously closed per video obtained of the accident (i.e., door was not open prior to accident).
 

Attachments

It'll be very interesting to see if there was any flight data recorded and what it showed, and how much power they think was being developed at the time of the crash. PT-6s are really hard to kill, with the exception of the fuel control issue I mentioned before.
 
flyingcheesehead said:
There is a failure mode with the fuel control unit that can cause a partial power scenario like this, and there's a "MAN OVRD" (manual override) lever right next to the throttle lever that should be advanced in that case. Again, possibly due to low time in type the pilot didn't recognize it and/or didn't remember to use it.
Click to expand...
I'm not going to speculate or pass judgement on any aspect specific to this accident; however, in general, the fact that not recognizing or forgetting to use a primary control for a known failure mode is worthy of consideration as a causal factor just screams of negligence or incompetence in operation and/or training.

Nauga,
who hopes for the best but trains for the worst.
 
They drilled us extensively on using the EPL (Emergency Power Lever) flying the PT-6 equipped T34C. When the IPs used to give us simulated engine failures, your hand would fly to that control fast...
 
Are there any turbine aircraft that don’t have a manual mode for a fuel control failure? Just asking…
 
Warlock said:
Are there any turbine aircraft that don’t have a manual mode for a fuel control failure? Just asking…
Click to expand...
Twins. I’m guess they figure you can just shut it down.
….

If the engine rolls back and settles at “idle” Ng (63% in the M600) it’s considered a “rollback” which is a failure in the FCU (fuel control unit). On the M600, they call it the “MOR” lever. “Manual OverRide”
 
Warlock said:
Are there any turbine aircraft that don’t have a manual mode for a fuel control failure? Just asking…
Click to expand...
AFAIK this is a PT-6 thing.

dans2992 said:
If the engine rolls back and settles at “idle” Ng (63% in the M600) it’s considered a “rollback” which is a failure in the FCU (fuel control unit). On the M600, they call it the “MOR” lever. “Manual OverRide”
Click to expand...
Yeah, we called it the MOR lever on the TBM too. Way quicker to say when you're reading the checklist.
 
Most PC-12’s have a “MOR” lever, up until 3 years ago when they introduced the NGX model, which has 2 channel FADEC fuel control.
 
Dave Theisen said:
Most PC-12’s have a “MOR” lever, up until 3 years ago when they introduced the NGX model, which has 2 channel FADEC fuel control.
Click to expand...
Yep, TBM 960 did away with the MOR lever too, and greatly simplified all the power controls for the pilot.
 
You must log in or register to reply here.
Back
Top