Single Engine Go-Around in a Seminole (or other light twin)

[CalifDan]

Bam?

LStorm2003,

You are right, I misread the initial post. However, my comments are still relevant. I think getting full flaps out without the "runway made" is what is critical. In your scenario, you lost 60 feet from the threshold to just over 600 fett down the runway. I think my math is correct in that that 600 feet is going to take something just over 4 seconds at 85 knots and your current rate of descent is 900FPM. You will interesct the runway in another three seconds without a flare at about 1000 feet down the runway. With power off, which I'm assuming you were even prior to the 100 feet over the threshold, you just might kill enough speed to flare and stop...but it will be tight. You are also going to run out of energy really fast so that 85 knots might actually help you arrest that sink rate. MY advice remains the same, land it.

DrinkDuff77...you are right, strike one was in choosing the short runway.

Ralgha...Back in the early days of my flight training they used to do engine cuts on take-off as part of the multi-engine sylabus. Many of those were Twin Comanches and many of them crashed. Enough so that the FAA changed the training process. As I noted above, with 900FPM down, full flaps, and no you are not going to go "BAM" flaps gone, I think it is unlikely that you are going anywhere. At least not for very long. I'm surprised to see a CFI suggest that if you can't do it (the scenario) you should not be in the aircraft. How many ME's did you train and do you have your name in their logbook? I hope they don't think that just because they got signed off they can do it. I can tell you that if you provided me that same advice on a training flight, I would discontinue our relationship and have a serious discussion with the flight school.

Go give it a try. Set up a hard deck at 3000 agl, and set up the descent at 900 fpm, 85 knots, and at 3040, give it a go. Your choice, you can start with your hand on the throttle or the flaps. My bet is you dip through 3000 before you even arrest much of the descent rate. I did my multi in a Senca II and we did this a number of times, but initiating from 200' agl. I got where I could beat it, but you had to be deliberate, thoughtful and just about perfect, and we were coming down closer to 500 FPM.

My intial multi instructor left me with some very good advice. Sometimes a multi-engine airplane is not, learn to recognize the difference early. Another more recent checkride instructor also gave me some good advice. He asked me what was the first thing I think of when an engine fails. I recited the checklist and he told me I was wrong. He said the first thing you think of is "What is this going to cost me?". His point was, if you are good enough to think that irst, you are going to do everything else right.

 

[minitour]

Don't forget you can fly in ground effect over that body of water.

Go around the boats, though.

That, to me, was the deciding factor.

Water usually doesn't have any obstacles out there unless you hit a bridge or oil rig...use the ground effect to clean it up at blue line and get climbing out.

Is it a slow climb? Yep. Should you have chose another runway? HELL yeah!

Is it doable? Most likely...depends on what the climb gradients are. I'd also be checking accel/go charts for my destination in that situation. If you're in the shaded area (such as in the Duchess POH), I'd be planning an "oh sh!t" alternate...just in case.

JMHO

-mini

 

[Lead Sled]

Strike one was really choosing to land at that airport. Why not go to one with a longer runway?

You win the prize today. As you move up the ranks of aircraft complexity, the aircraft don't get hard to fly, they actually get easier. However, they do require enhanced judgement - the penalties for error are much greater. Operating a light twin off of a runway that would put you in the situation that Mini described doesn't show me a lot of judgement. The biggest challenge a professional airman faces in day-to-day operations isn't the actual flying of the airplane, it's knowing when to say "no".

'Sled

 

[DC8 Flyer]

Guys,

I was wondering how you all feel about this... Let me set the scene for you...

You are making a single engine approach to land at an airport with an elevation of 50ft MSL. Density altitude is about 900. Your aircraft is at about 250 pounds under max gross weight and the failed engine is feathered.

Unfourtunatly the runway is only 2500 feet with no over-run and there is a body of water when the runway ends. The gear is down, the flaps are extended, you are at about 100 feet when you cross the runway threshold, you think you have the runway made, but then suddenly the wind shears from a negligible headwind to a 15 knot tailwind. Your aircraft initially descends but now you are using runway fast, since your ground speed has increased! You are now at about 40 feet AGL, 85 knots IAS, with a little less than 1/4 of the available runway behind you.

Do you attempt to force the aircraft onto the ground with this tailwind? Or do you attempt a single engine go-around?

Comments?

It was said before, bad choice of airports, BUT that may have been the only piece of pavement available within range.

This is a good scenario argument. 40' AGL is a little less than a "short field" landing distance performance problem. I dont have my PA44 POH anymore, but the longest disance I ever remember using was 1500' (max for the chart I think). You have about 1600 feet of runway in front of you, land on the darn thing. A go around in a SEMI with gear down and full flaps, at 40' AGL is going to be tricky. You are going to have to arrest a 500 fpm decent with, about negative 300 fpm worth of drag hanging out. You can probably do it, and fly in ground effect over the water, but whats at the other end of the "lake"?, usually a rise in terrain with trees. A semi is no Airbus when it comes to cutting through trees.

Plant that beast and melt the breaks if you need to.

 

[djsk]

Gear down is the commit point. We used to practice ILS approaches to 50 feet because of this.

 

[NoPax]

Gear down is the commit point. We used to practice ILS approaches to 50 feet because of this.

Yeah...took me a little while and a few 'experiences' to realise there is no rush in putting the gear down - and forget about flaps, completely unnecessary.

One engine inop, or in icing...gear comes down when I'm landing.

The original question about the go-around, reminds me of another thread, where someone asked 'what would you do if you had full flaps, and were running out of runway - force a landing, or risk going around into trees?'. The answer/technique is irrelevant, as both would involve a skill you didn't have to begin with - a "double negative". In the above situation, you'll either crash in the water, or crash trying to 'force' it on the runway, either way...........you're crashing.

 

[Vastly Underemp]

FAA says you will land in the first 1/3 of the runway or go around....period.

 

[CalifDan]

First 1/3?

I don' recall an FAR regarding the first 1/3 of the runway.

Many years ago I occasionally flew my Mooney into SFO. Kept up 130 knots until over the threshold and landed in the final 1/3 of 28R (I think thats it) with a quick exit at the end to Butler. The tower staff seemed to appreciate the blend and apparently they didn't know about the "rule" either, because they never asked me to call them.

 

[DC8 Flyer]

FAA says you will land in the first 1/3 of the runway or go around....period.

Not quite period. Single engine in a PA44 is an emergency situation. First 1/3 of the runway be damned. Of course if you are really caught up in it, you could always ask for a long landing.

 

[paid4training]

I fly a Duchess which is similar performance to the Seminole. Actually, my single engine service ceiling is higher, so rate of climb in this situation might be slightly better.

My Duchess manual says about 2000 feet to land over a 50 foot obstacle given the scenario you outlined prior to the wind shear. At 100' over the threshold, you aren't going to land on that runway even without the wind shear issue. This would be particularly true at 85 knots, however, I understand why you might want to stay at that speed. The decision to go around should be made much sooner. Strike One!

In this scenario you are at full flaps prior to having the runway made. 100' over the threshold on a 2500 foot runway is not having the runway made. Strike two!

Now you are down 3/4 of the runway at 40', 85 knots, and thinking time to go-around. You may well be in the water by the time you get up the power and take the hit from retracting that first notch of flaps. Are you sure you want to go for strike three?

When I was checking out in the Duchess my instructor did an engine cut on take-off at about 400 feet. Things went pretty well. The Duchess takes off with flaps up and all that really needs to be done is to get the gear up and secure the bad engine. In that scenario, the gear was already up and he set zero thrust. Slow climb to pattern altitude and I started setting up the approach. It was a nice Texas day with winds at about 30 knots gusting higher and not down the runway. Base was into the wind.

Gear down, first flaps on downwind, turn base, added the rest of the flaps on base and suddenly realized that this turkey was not going to get to the runway. I expressed that concern to the instructor and his response was "Well, what are you going to do?". I told him I needed to get rid of the flaps and he said "You better get going". I could not believe how much altitude I had to trade to get rid of the first 10 degrees or so of those flaps. We made the runway, but we would not have if I had left the flaps at full.

My personal opinion, if you decide to try the single engine go-around at the place and configuration you have postulated, be careful, watch out for VMC and make sure you ditch before you loose control. Your chances of striking out are very high, very very high.

If you ask me what I would do in that situation, I would tell you that I already made the decision to land when I put out the last of the flaps. Or, I would have gone around when I realized that I could not cross the threshold below 50 feet. The scenario you have created is the killer scenario.

Did he perform a drag demo to show you the difference in your sink rate/climb performance? During a drag demo you should see and hopefully the following info...

From clean slow flight you pull the left engine to "zero thrust" other engine to 20'. Put the gear down and notice the sink or climb rate increase power on good engine about 25'. Put the flaps down and add full power and notice the sink rate. Raise the gear and notice the sink rate with flaps out. Then after you put the gear up decrease left engine to idle to simulate windmilling prop. This would demonstrate the gear has less sink rate (due to assistance from keel effect) and the windmilling prop (adverse drag)the most sink rate with the flaps somewhere in the middle. During my trials I noticed the airplane (during the current Atomospheric conditions) my flaps did allow a sink rate and if you are close to the ground you need all the help you can get. During all my simulated engine out demos I never used flaps. Its all about speed control, maintain blue line all the way to the runway. Gear out at the last minute (of course allowing for the gear to go down and lock) runway made throttle back....etc

During the engine out proceedure you should establish blue line and hold it because it will give you the the best single engine climb rate...or at least in the pig I was flying. The duchess may have a different blue line speed but the proceedure is the same.

Just my .02 cents...