Engine out on approach – would YOU make the runway?

[IrishAl]

Incident in Florida today:  Irish aviators crash on approach due to engine out.

http://www.bbc.co.uk/news/uk-northern-ireland-29241991

 

 

One year ago, a similar incident occurred at the home club of the pilots of this plane. 

 

A Tecnam Sierra suffered an engine out on final and crashed in a park short of the runway. (No fault with the 912 was found, so it was attributed to icing.)

http://www.bbc.co.uk/news/uk-northern-ireland-23457961

 

Question: why do most aircraft arriving at an airport end up needing power on final to make the field?   It makes no logical sense to put yourself in a position where you’re dependent on the engine, especially as loads of altitude has just been dumped.  

 

Yet, this is how everyone flies, it seems - even the airlines do it.  In 2008 a Boeing 777 suffered an engine out on final (fuel freezing, I believe) and it crashed just short of the runway at Heathrow.  If it had had just a little more altitude, it would have made it.

 

Why is it not standard practice to adopt a steeper approach that would ensure the runway can be made in the event of an engine failure?   

[Anticept]

My speculation:

• Idle power puts out more thrust than people think, and runway overruns are a good source of accidents too. Since power off approaches are much much much more common than engine out, the theory might be that it is safer to avoid steep approaches than it would be to account for the extremely rare engine out situation.
• Easier to see the deck over the nose in old airplanes, so we ended up sticking with 3 degrees.

[GravityKnight]

Seems runway dependent. If I have plenty of runway, I prefer to come in without power/steeper and if I float a little, so be it. At my house it's a little trickier.. short field, power lines to clear... though I don't see why a person couldnt figure out the flap/approach angle that would guarantee clearing obstacles and not carrying a bunch of extra energy.

 

Of course conditions can change this.. I like extra speed when it's windy (as I'm sure most of us do)

 

I always try to cut the power a-beam a runway and fly it in at idle.. but that brings up another point,

 

 

 

Idle power puts out more thrust than people think

 

This seems like a really good point. One of the LS's I fly has much less prop pitch than the other LS/SW. Just that difference makes a huge difference if coming in with idle power. I haven't had to come in engine off thankfully   But that would make a pretty large difference over idle, and kind of not something people practice...

 

 

 

Speaking of approaches.. I want to get into more off airport type flying. I love STOL stuff. This video is interesting... check out the approach they are talking about making in this video: https://www.youtube.com/watch?v=CrPJac80W9Y  Thoughts?

[Jim Meade]

Some people like to land on the numbers with power. Lose power and face a strong wind and you won't make the numbers. It's better to use the aiming point and plan to touch down at the touchdown point, giving one's self a little cushion if you lose power on short final.

People are taught much bigger patterns than they used to learn 30-40 years ago. Thus, a long final which requires some power - lose it and you lose it.

The FAA started pushing the stabilized approach, a concept really more applicable to large planes, but it got morphed into long finals under power, which is not really what the stabilized approach is.

I routinely practice dead stick landings (I am not advocating it, just saying) and it is correct that loss of idle power makes a difference.

[FlyingMonkey]

I think if I had an engine out in the pattern on a long runway, I'd aim nowhere near the numbers, I'd probably shoot for a third of the way down the runway...would be safer and give plenty of margin for glide slope judgment errors in either direction.

[Doug G.]

I think Jim was addressing where you normally aim on final to anything that is not a short runway. I usually aim for the numbers, but the touchdown point is a bit farther down the runway. I may rethink that.

[Jim Meade]

AIM figures 2.3.1 and 2.3.2 illustrate the aiming point and touchdown zone in relation to the numbers and runway end.

AFH says on 8.2 to land in the center of the first third of the runway.

Like many, I was started out aiming for the numbers. I do some very short field landings routinely on certain strips, but at bigger ones I'm trying to make myself fly an approach that has me touching down farther in than the numbers.

[cdarza]

Did an intentional engine out - just because.  Started at 3000 ft - with an airfield below incase no engine restart.  0 flaps, 60kts glide, 500ft/min sink rate.   Only thing i forgot to do was notice how much altitude lost in a 180 degree turn.   CTSW has a nice glide. 

 

[sandpiper]

Conditions permitting, I am at idle thrust and flaps 30 abeam the numbers with 50K on final. I shoot for the numbers on our 3000ft strip but even at 50K get some float. Ideal touch down is with the nose wheel held off.

 

Once I close the throttle abeam the numbers my goal is not to add back any power. Doesn't always work.

 

Fifty years ago when I got my PPL I was taught to always be able to reach the runway if the power fails. Shortly after that my Uncle taught me to do the same in his helicopters. The instructors lived for the opportunity to chop the throttle when you wern't able to do that. You then got rewarded with a low grade for that days ride.

 

Anyhow, these early lessons stuck. Law of primacy I think.

[Marco01]

I have spent some time to identify my CTSW gliding best performance with engine off: speed at 117km/h and flap set at 0°C. I have then set the right gliding ratio in my Ipad Skydemon software: 1:11 (no safety margin). when flying, if engine is out: I would immediately check if any airfield are in the blue circle: yes, I will go there, no: I will look for the best field.

Back to the threat, when Flying in the pattern, the blue circle will always give a good view if I'm safe to land if the engine quit, even in final. In reallity, I'm not looking at the ipad in the pattern, and prefer to focus on landing, but always above the standard slope uses by general aircraft: if too high, I can use 40° flaps plus light slip.

[gbigs]

Some are making the mistake assuming more flaps equals better glide.  It's the opposite...from the POH.

 

Section 5.2.4 Gliding Characteristics

Glide angle of the CTLS can be assumed to be 8.5:1 with flaps 0, 7.9:1 with -6.  With flaps further extended this ratio gets worse (drag versus lift).

 

Speeds for best glide vary with weight.  At 1100lbs at flaps 0 best glide speed/pitch is 65kias. 

 

So, the best engine out strategy is to pitch for best glide based on weight and speed with flaps 0.  Once the runway is made, adding more flaps may be okay as long as you remember you get a pitch up moment when changing flap settings.

[Tom Baker]

My assumption is that your assumption that some are assuming flaps equals better glide is wrong. Also as a side note not everybody is flying a CTLS, so what your POH says may not apply to what others are flying.

[IrishAl]

Marco,

That's a great feature of Skydemon!

[sandpiper]

My assumption is that your assumption that some are assuming flaps equals better glide is wrong. Also as a side note not everybody is flying a CTLS, so what your POH says may not apply to what others are flying.

Ditto squared.

[WmInce]

My assumption is that your assumption that some are assuming flaps equals better glide is wrong. Also as a side note not everybody is flying a CTLS, so what your POH says may not apply to what others are flying.

 

Ditto cubed.

[Marco01]

Marco,

That's a great feature of Skydemon!

Yes it is! Size and shape of the circle will change life accordingly to the topography, with strength and direction.

In the land around is perfectly flat, and no wind, plane position will be at the middle of the circle, if wind is present, plane position will be not centered anymore, and if you are flying in mountains, shape of the circle will be modified according to the valleys.

I ran several test under several wind condition, ie flying 3000 ft, and position my plane at the circle ridge, then stop engine, and see if I can make the fields: it worked!

The beauty is that, while gliding, you can constantly check if the airfield stays in the circle, if not (for example if the wind considered by the software was underestimated), then you know you need to consider an other option before it is too late.

Attached some additional pictures...

[Marco01]

Yes it is! Size and shape of the circle will change life accordingly to the topography, with strength and direction.

In the land around is perfectly flat, and no wind, plane position will be at the middle of the circle, if wind is present, plane position will be not centered anymore, and if you are flying in mountains, shape of the circle will be modified according to the valleys.

I ran several test under several wind condition, ie flying 3000 ft, and position my plane at the circle ridge, then stop engine, and see if I can make the fields: it worked!

The beauty is that, while gliding, you can constantly check if the airfield stays in the circle, if not (for example if the wind considered by the software was underestimated), then you know you need to consider an other option before it is too late.

Attached some additional pictures...

[ralarcon]

Some people like to land on the numbers with power. Lose power and face a strong wind and you won't make the numbers. It's better to use the aiming point and plan to touch down at the touchdown point, giving one's self a little cushion if you lose power on short final.

People are taught much bigger patterns than they used to learn 30-40 years ago. Thus, a long final which requires some power - lose it and you lose it.

The FAA started pushing the stabilized approach, a concept really more applicable to large planes, but it got morphed into long finals under power, which is not really what the stabilized approach is.

I routinely practice dead stick landings (I am not advocating it, just saying) and it is correct that loss of idle power makes a difference.

Great thread guys ! My CFI likes the steep approach concept and that is how I learned to land. Since then I have tried both. I have come to the conclusion that for me, in Florida the steep approach is best. I have a particular anecdote. Florida weather , produces frequent updrafts and downdrafts. Once I was landing at KVNC, runway 23. This is an over land (town) approach , as opposed to the other approaches over the beach. This is a notorious drafty approach. I was flying with my CFI post Solo. I encountered a very strong downdraft that required WOT, just to smooth the descent . Had my approach on final, been flatter, I'm convinced I would not have made it to the runway. To the point that my copilot said, after landing, he thought I was going to go around. However I was able to keep a stable approach and cut off power over the numbers, with a safe soft landing. Therefore I use mostly steep finals, and if I'm to high , I just slip the airplane and quickly I'm where I want to be. As a second benefit it also helps me make the runway on idle if I choose to do so. It just works for me, here in Florida. I'm sure it is different in different weather and of course different runways.

 

Cheers

[Ed Cesnalis]

• I chop the power when abeam the numbers
• 30* flaps - Approach and land
• Beat myself up
  • I needed power to make the runway
  • I made the runway but landed beyond the numbers

 

OR

• Good job
  • float over the threshold and land on the numbers

[ralarcon]

 

• I chop the power when abeam the numbers
• 30* flaps - Approach and land
• Beat myself up
  • I needed power to make the runway
  • I made the runway but landed beyond the numbers

 

OR

• Good job
  • float over the threshold and land on the numbers

 

I have not used 30 (to land) Flaps since I was practicing short field landings , when I was a student. I use 0 to 15 deg. flaps about 50/50 depending on crosswinds. Used - 6 once and it was a non event.

 

Cheers

[FastEddieB]

I have not used 30 (to land) Flaps since I was practicing short field landings , when I was a student. I use 0 to 15 deg. flaps about 50/50 depending on crosswinds. Used - 6 once and it was a non event.

 

Cheers

I will make my customary observation:

 

Unless you can articulate a very good reason to land with partial flaps...

 

...less flaps = faster touchdown speed = more energy carried into the landing = more probability of injury or death if something goes wrong.

 

Hitting a deer at 50k is a whole lot different than hitting it at 39k, let's say.

 

Not to mention the relevance to this thread's topic - the only good place to land may be 800' or so and proficiency with full stall/full flap landings could be a lifesaver - maneuvers are a lot more difficult if not practiced regularly.

 

I think most shy away from full flap landings because they seem harder. Well, they are harder if you don't know how to do them safely and consistently. If you do know how to do them well, they're safer overall - conditions permitting, of course.

 

But this is an old debate and I've made this point before. It's highly unlikely to change anyone's habits. Mainly repeating it again for any newcomers or new pilots - it's that important.

[coppercity]

We have beat this topic up plenty.  A couple reminders about the CT landings with full flaps.  First they are not especially hard to do and any CT pilot should be comfortable with performing them but under the right conditions i.e low crosswinds and stable air.  The CT has a very low Vfe for flap settings greater than 15 deg so can be easy to overspeed the flaps if a high descent rate is needed.  Stall speed is of course reduced as well as approach and touchdown speed so in gusty conditions the CT can be a hand full near the ground at these low speeds that's why a 15 or 0 flap landing is preferred as crosswinds and gusts increase.  The aileron flap coupling of the CT seems to reduce the aileron effectivness in stronger crosswinds and high flap settings which leads to unwanted drift during and after touchdown.  Students and newer CT pilots tend to balloon more during the round out with higher flap settings and steeper approach, this is followed by a relatively hard landing with the rapid speed loss during the balloon.  Go out, have fun and practice landings at all flap settings just be cautious of the conditions when using the higher flap settings in the CT.  Its not your typical Cessna   

[FastEddieB]

Hence the "conditions permitting" caveat!

[Tom Baker]

I will make my customary observation:

Unless you can articulate a very good reason to land with partial flaps...

...less flaps = faster touchdown speed = more energy carried into the landing = more probability of injury or death if something goes wrong.

Hitting a deer at 50k is a whole lot different than hitting it at 39k, let's say.

 

Not to mention the relevance to this thread's topic - the only good place to land may be 800' or so and proficiency with full stall/full flap landings could be a lifesaver - maneuvers are a lot more difficult if not practiced regularly.

I think most shy away from full flap landings because they seem harder. Well, they are harder if you don't know how to do them safely and consistently. If you do know how to do them well, they're safer overall - conditions permitting, of course.

But this is an old debate and I've made this point before. It's highly unlikely to change anyone's habits. Mainly repeating it again for any newcomers or new pilots - it's that important.

Eddie, I think the risk of hitting a deer during landing is far less than that of having a hard landing trying to use full flaps, especially for new comers or new pilots. I am basing this on instruction provided to many different students in the CT series aircraft.

 

From full flaps to -6 the stall speed only varries by 5kts, and using 15 degrees instead of full flaps only creates 1-2 kts difference. This sure doesn't agree with your sugestion that landing with partial flaps will cause you to land at 50 kts. Propper technique during landing has a far greater effect on touchdown speed than flap setting.

 

You often preface advice by saying "Any other aircraft I have ever flown". I can tell you based on 35 years flying and over 7 years operating CT's that the CT is not like every other aircraft. Treating the CT like every other aircraft is a good way to have a bad day.

[FastEddieB]

Point taken.

 

Pilots are free to land at any flap landing they choose, at any speed they choose.

 

If an owner is uncomfortable with full flaps, they should be avoided.

 

If I owned a CT, I'd want to be proficient at all the flap settings, including the maximum. I'd assume they were put there by Flight Design as a tool to get maximum performance from their planes. And I like to practice maximum or near maximum performance on nearly every landing, so if and when I need it I won't be rusty.

 

The 50k reference came from prior discussions where some CT pilots liked to land...

 

1) With partial or no flaps...and...

 

2) Carrying power...and...

 

3) With a preference to "flying it on".

 

All of which is fine. But I'd call them bad habits with cumulative effects that someday just might bite someone.

 

But I'll leave that there, since this is a rehash and anyone who cares can find volumes of arguments on both side with a fairly simple search.