In the MU-2, the 400AGL I mentioned in an earlier post is considered a "hard" number (perhaps somewhat like the 747 example). When doing the SFAR training, MU-2 pilots are taught to do the single engine instrument approach at 5 degrees of flaps, never selecting 20 degrees unless you break out and see the runway. You are instructed not to attempt a single engine go-around below 400 feet. Therefore, my instructor had me use 400 AGL as the DA even if the approach you were flying was an ILS with a 200 foot minimum. This assumes of course that you have better weather somewhere else and the fuel to get there.

A 200 ft altitude mistake kills you in one case, not the other.

So therefore, I'd argue the 800 ft missed requires less skill to NOT DIE.


That's a decision I make after going missed.

With one engine operating, I have no less propulsion redundancy than a PC-12 or TBM.

I could fly all the way back to KCEF with a 12000 ft runway and 2000 overcast weather if I want.


From 800 ft (postulated engine failure altitude) to 345 ft (approach minimums) is about 35 seconds on the glideslope.

If you want to do the engine failure procedure/checklist, AND fly the approach laterally and vertically to the absolute minimums, AND visually search for the runway, in that time, go ahead.

I prefer to go missed which removes at least one axis (glideslope) from my piloting chores, as well as the visual runway search. Now I power up, gear up, secure the engine, climb out and sort out my next move not in a highly compressed and critical situation. I need only track my lateral course, so I have task shed quite a bit.

My plane will give me 900 FPM one engine out under these conditions. I'll be back at approach maneuvering altitude, 2000 ft, in 90 seconds. Only when reaching 2000 ft do I need to do anything else on the missed, so I got a little bit of time.

Mike C.

Since we use flaps 20 on routine dual engine approaches, this means an engine failure on glideslope is somewhat misconfigured for a single engine approach due to flaps 20 instead of flaps 5 that is preferred.


The 400 ft number is conservative since it covers all conditions, but the point is having spare altitude provides margins to reconfigure for missed.

The Inhofe accident was a plane configured for landing (gear down, flaps 20) and lost an engine at 1500 ft AGL in severe clear weather. If his mind set was "I'll save the approach", then that would explain the gear left down and the flaps left at 20. But that didn't work and he could not hold course or altitude.

Instead, if Inhofe had a mind set of "abort the approach, come back around properly reconfigured for SE", then I think there is a far better chance he secures the failed engine, raises the gear, speeds up, raises flaps, and comes around to shoot a proper SE approach. This strategy thus requires focusing on ONE thing, an SE climb out, then another ONE thing, SE approach, in sequence, instead of trying to do both at the same time.

Leaving the gear out sealed his fate. I was able to recreate his conditions and my plane WILL climb gear out, flaps 20, but drop 10 knots from ideal airspeed and it won't any more. Pull the gear up, no problem, lots of climb and easy to accelerate to flap retraction speeds.


Even if not, aborting a situation where you are flaps 20 gear down and coming around to shoot the SE approach at flaps 5, even to the same runway, you are still better off, due to being properly configured for SE approach.

Mike C.

This is exceedingly similar:

In the case of the one-engine-inoperative landing, Beech makes it clear that the selection of full flaps cancels the go-around option. Granted, why would we ever choose to make a single-engine go-around? With proper runway and weather selections, the need for that maneuver should be exceedingly low. But, on the other hand, when the Airbus we’d been following blew a couple of tires, stopping on and blocking the runway, wouldn’t it be nice to do an uneventful go-around and either use another runway or even another airport? However, if we’d already gone to full flaps, then we’d better land in the grass or on a taxiway beside the blocked runway.

This from here:

http://kingairacademy.com/landing-approach-speed/

So the King Air is similar, avoid heavy flaps when single engine. When you do go full flaps, your go around option is canceled.

This is one reason I'd prefer to go missed, clean up, and reshoot the approach with flaps 5.

Mike C.

I think this has gotten to the “nit picking” stage to some extent.
Mike, I think you may have misinterpreted my reason for posting the 400 foot “hard” limit on a SE approach. I was responding to Steve who had mentioned that it would be better to continue down to approach minimums of 200 feet. Certainly continuing a SE approach to 200 and then conducting the missed is possible, and if you are keeping your speed up it’s probably going to work out, but the SFAR commands a more conservative approach to go missed at 400 feet.
I would agree that you have more “wiggle room” by doing the missed at 800 instead of 400, but you could argue that same thing at any point in an approach...engine failure: go missed (regardless of your altitude and position on the approach). Get a delaying vector, run the checklists and get mentally prepared for a SE approach, come back and do it. That is certainly appropriate in some cases. But if you loose an engine late in the approach, as you stated, it may only be about 30 seconds from failure to landing (or go around). Clearly not enough time to run a full engine out checklist, but if the ATIS suggests you will likely break out before the 400AGL suggested DA, and you are late in the approach, I’d certainly favor pulling the CL to feather and advancing the PL and doing nothing else until I’m on the ground instead of powering up and climbing out. This is especially true if there is snow (which around here is pretty much the only reason I have to do approaches and there is always ice...sometimes bad, usually trace). If you get to 400 feet and need to go around, you are already at 135 so you can immediately go to 5 degrees, and pull up the gear as you power up and go around.
Unfortunately, messing up the go-around and erroneously not electing a go-around are two of the major contributors to aviation accidents so this is certainly a pertinent discussion. The words of my initial instructor in the MU-2 are in the back of my head with every approach...he told me to tell myself before I start each approach “if you have to go around, it’s no big deal.” That way you are mentally prepared and somewhat more relaxed about the decision. But I really feel that going around at 135kts and 400 AGL in an MU-2 is really a pretty safe exercise and quite conservative. Doing at 800 is even more conservative, but you might be foregoing the opportunity to get the plane safely on the ground before whatever caused the engine failure takes out something else or affects the other engine. Just my opinion on the matter of course.

Don't forget you are already at flaps 20 when the engine failed.

The AFM says not to attempt a go around after selecting flaps 20, nor under 400 ft regardless of flaps.

And you are flying down a glideslope to an uncertain approach in weather that is already known to be wrong, and in heavy rain.

Dicey.

You can hold the glideslope, there is enough power to do that gear down, flaps 20, but when you want to go around, you are gong to descend below MDA as you suck gear up, then establish a climb but you want to speed up to get to where you can retract flaps to flaps 5.

It can be done, no question. But my judgment says, at 800 ft, abort the approach while I still have altitude to work with, assess my choice of runway, perhaps fix the engine problem, and even if I come back to the same runway, I can now do this as a single engine approach from the start, at flaps 5.


On the video approach, 400 ft MDA would likely have meant a go around, runway was not in sight at that altitude.

An additional task: recompute MDA to include the 400 ft limit. It is amazingly easy to make arithmetic errors while concentrating on something else like flying an approach with a failed engine.


It is definitely a judgment call based on the situation and part of that would be the circumstances of the engine failure.

I've read a bunch of accident reports and one thing that comes through to me is when a pilot makes choices based on hoping things will get better instead of limiting the worst case. Staying with the approach, even though you already know the weather info you have is wrong, is making a choice hoping you will make it in. In these exact circumstances, I prefer to make a choice which assumes the worst and improve that by going around. By aborting and going around, I avoid the worst case scenario of being at minimums, heavy rain, and having to go around with higher drag than usual when single engine.

I feel like aborting "breaks" the accident chain, resets the situation. I now have time to think, consider my options, and settle on a better one than if I had stayed on the approach.

I do not think those who chose to continue are wrong in their choice, it is just not how *I* would handle it under these exact circumstances.

Mike C.

Mike,

Consider your choices if you had SV...then what?

Hmm, not sure I want to mix braille flying with an engine out.

Don't think that would change much. I'd rather go around and seek better weather outright than combine the emergencies of engine out and busting minimums.

There are times when going below minimums is the least risky option available. I didn't feel this case would be that.

Mike C.

Thomas,

I think you stated the issue well. I took the time to read the SFAR, and what it looks like to me is that in response to the MU2's accident record, FAA developed the program that has wide safety margins, and it was sure to reduce the accident rate, compensating for previous ham fisted pilots.

I think the SFAR formal training it self is well designed, and the graduates of the training program are a step ahead of previous MU2 pilots without any or much formal training, with an accident record that reflected it.

There is a lot of emphasis on single engine landings, but from what I've read most of the MU2 accidents were planes that were fully functional, with just poor pilot technique and airspeed control.

I found it strange that for the MU2 checkride the precision approaches are to instrument rating tolerances, but they want a Cirrus pilot to fly to ATP standards. I think a Cirrus pilot new to the plane is far less likely to get in trouble with it than a pilot new to an MU2.

This is an odd discussion. What mike suggests makes so much sense. A go around higher gives you a bigger margin of safety. Losing an engine in the mu2 is not a huge deal, however, if above 400 feet why not go missed and calmly sort things out? Why the rush to get on the ground?

My understanding is that the MU2 training program (now part 91 subpart N, no longer an SFAR) is done to commercial tolerances.

At least, that is what the instructors have stated in the past, and they decide on the tolerances for passing.

Mike C.

It depends on the weather in the area. You can add so much to the DA that you might not get into an airport in an area of wide spread low ceilings and visibilities. Why not go missed and calmly sort things out? If you have a failed engine (mechanically failed), it will still be failed on your next approach.

Your filed alternate was at least forecast to be higher.

Redoing the approach won't make the ceiling worse, plus the plane will now be more properly configured for SE flight, and you are mentally prepared for it.


Not necessarily. There are cases where you can restore the engine power for some set of failures. An example would be a flame out due to heavy rain, and auto ignition was inadvertently left off or didn't function. That's a relatively easy fix, do an airstart.

At worst, you still have the same approach, so you are no worse off than you were before, but now you are going in knowing it is single engine.

Lots of accidents come from tunnel vision, concentrating on the narrow view in front of you and missing the big picture. Going around allows a reevaluation of runway, weather, airport, situation. Expands your vision so you can make a better informed decision.

I think a great many accidents would be avoided if, at some point during the sequence, the pilot had taken 30 seconds to examine their condition from a high level and ask them if the current trajectory is the right one. "Am I doing the right thing here?" A lot of the time, the answer will be "no, do this instead". It amazes me how often I read an accident report where that question is never seemingly asked by the pilot.

The old adage about emergencies was "first thing to do is wind the watch". The meaning is, take some time to consider the situation, do not rush into a course of action too quickly. Outside of very few cases, quick and prompt action by the pilot isn't required in most emergencies and doing the wrong thing quickly makes it much worse.

Engine fails on this approach at 800 ft, I'm going missed, winding the watch, and then enacting a carefully considered plan. That plan may be no better than doing the approach again single engine, but it certainly will be no worse, and I will be mentally in a much better place to handle it.

Mike C.

Your filed alternate was at least forecast to be higher.

Redoing the approach won't make the ceiling worse, plus the plane will now be more properly configured for SE flight, and you are mentally prepared for it.


Not necessarily. There are cases where you can restore the engine power for some set of failures. An example would be a flame out due to heavy rain, and auto ignition was inadvertently left off or didn't function. That's a relatively easy fix, do an airstart.

At worst, you still have the same approach, so you are no worse off than you were before, but now you are going in knowing it is single engine.

Lots of accidents come from tunnel vision, concentrating on the narrow view in front of you and missing the big picture. Going around allows a reevaluation of runway, weather, airport, situation. Expands your vision so you can make a better informed decision.

I think a great many accidents would be avoided if, at some point during the sequence, the pilot had taken 30 seconds to examine their condition from a high level and ask them if the current trajectory is the right one. "Am I doing the right thing here?" A lot of the time, the answer will be "no, do this instead". It amazes me how often I read an accident report where that question is never seemingly asked by the pilot.

The old adage about emergencies was "first thing to do is wind the watch". The meaning is, take some time to consider the situation, do not rush into a course of action too quickly. Outside of very few cases, quick and prompt action by the pilot isn't required in most emergencies and doing the wrong thing quickly makes it much worse.

Engine fails on this approach at 800 ft, I'm going missed, winding the watch, and then enacting a carefully considered plan. That plan may be no better than doing the approach again single engine, but it certainly will be no worse, and I will be mentally in a much better place to handle it.

Mike C.

Stop & feather...then either land or wind the watch, whichever you prefer. That was the lesson from the Red Lake Metro accident.