Forced Approach.
Moderators: North Shore, sky's the limit, sepia, Sulako, Right Seat Captain, lilfssister
Forced Approach.
Okay, so on Forced Approaches, I have all the procedures nailed except for making the feild not too high/too low (The most importrant part...) any suggestions on changes I should make to be at the right height for approach/landing?
Re: Forced Approach.
"Aviate, Navigate, Communicate"
Usually if a student (or expierienced pilot) misses the forced approach landing by being off altitude the he/she is spending to much time on the checklist and mayday calls portion of the procedure. When your instructor initiates the forced approached take time to asses the situation visually, pick you field, don't rush this. Then you can run through your why isn't my airplane working? List. Re-asses the flying situation. Make sure your on line for where you want to be. Then, continue on to your calls. Hopefully you can get all this stuff done in plenty of time to leave the last part of the trip strictly for Aviating to make minor corrections to your approach path, slight variations for winds etc....
But always remember, you need to fly first, do other stuff second. Don't get caught up in trying to do all the secondary stuff first. In a real situation like this it won't do any good to have run through all your checklist items perfectly only to splatter yourself like a bug on landing because you forgot to look out your window and fly your airplane.
But free advice is free for a reason.
Give
Usually if a student (or expierienced pilot) misses the forced approach landing by being off altitude the he/she is spending to much time on the checklist and mayday calls portion of the procedure. When your instructor initiates the forced approached take time to asses the situation visually, pick you field, don't rush this. Then you can run through your why isn't my airplane working? List. Re-asses the flying situation. Make sure your on line for where you want to be. Then, continue on to your calls. Hopefully you can get all this stuff done in plenty of time to leave the last part of the trip strictly for Aviating to make minor corrections to your approach path, slight variations for winds etc....
But always remember, you need to fly first, do other stuff second. Don't get caught up in trying to do all the secondary stuff first. In a real situation like this it won't do any good to have run through all your checklist items perfectly only to splatter yourself like a bug on landing because you forgot to look out your window and fly your airplane.
But free advice is free for a reason.
Give
Re: Forced Approach.
Oh Yeah, and cheat like crazy with sideslipping and flaps if you're to high.
And if you to low.....try "clearing" the engine one last time.
And if you to low.....try "clearing" the engine one last time.
Re: Forced Approach.
This is something that could REALLY happen to you and you shouldn't rely on prolonged "clearing of the engine" to save you. Seriously.
Try taking something you're familiar with and applying it to a forced approach situation.
You have flown lots of circuits, and by this time you probably can judge how far you need to be from your touchdown point at your downwind to base turn when your altitude is about 1000' AGL.
While FLYING THE AIRCRAFT, choose a touchdown point and 2 key points where the downwind to base turn in a circuit would be, one for a right hand approach, one for a left hand approach. (A common error is to pick this points too close to the field, so watch for this.) Fly to the closest point. As you reach it, make a decision if you're going to carry on to the other chosen downwind-to base turn point, or, fly the base leg and then the final leg, keeping several factors in mind.
1) around 1000' AGL - you should be able to fly the "usual" base and final leg, cutting the corner if the headwinds are strong or if you're slightly low, or using s-turns/slipping if you're high.
2) if you're above your "circuit altitude" by 1000' or more, fly to the next key point, and reassess.
3) if you're above your "circuit altitude" by less than 1000', do some manoeuvring (s-turns, etc) to lose altitude, since you won't have the altitude to fly to the next key point... keep in mind, you want to be at your "final" turn point at about 500' AGL, just like a circuit, so don't get too low.
This technique works well as an initial way to teach forced approaches because it likens it to a circuit, there is no constant turning motion so it is more simple to carry out the engine failure drill and radio call, etc, and is somewhat familiar.
Common errors - picking your key points too close to the field, and failing to properly trim the aircraft while gliding.
This is by no means a complete lesson, so talk to your instructor about this.... I must say though - if the technique your instructor taught you isn't working, they should be trying a bit harder to find something that works for you. There are a million (well... maybe not quite that many) ways to deal with a failed engine and what works in one situation may not work in another.
There - that'll be $50.
Try taking something you're familiar with and applying it to a forced approach situation.
You have flown lots of circuits, and by this time you probably can judge how far you need to be from your touchdown point at your downwind to base turn when your altitude is about 1000' AGL.
While FLYING THE AIRCRAFT, choose a touchdown point and 2 key points where the downwind to base turn in a circuit would be, one for a right hand approach, one for a left hand approach. (A common error is to pick this points too close to the field, so watch for this.) Fly to the closest point. As you reach it, make a decision if you're going to carry on to the other chosen downwind-to base turn point, or, fly the base leg and then the final leg, keeping several factors in mind.
1) around 1000' AGL - you should be able to fly the "usual" base and final leg, cutting the corner if the headwinds are strong or if you're slightly low, or using s-turns/slipping if you're high.
2) if you're above your "circuit altitude" by 1000' or more, fly to the next key point, and reassess.
3) if you're above your "circuit altitude" by less than 1000', do some manoeuvring (s-turns, etc) to lose altitude, since you won't have the altitude to fly to the next key point... keep in mind, you want to be at your "final" turn point at about 500' AGL, just like a circuit, so don't get too low.
This technique works well as an initial way to teach forced approaches because it likens it to a circuit, there is no constant turning motion so it is more simple to carry out the engine failure drill and radio call, etc, and is somewhat familiar.
Common errors - picking your key points too close to the field, and failing to properly trim the aircraft while gliding.
This is by no means a complete lesson, so talk to your instructor about this.... I must say though - if the technique your instructor taught you isn't working, they should be trying a bit harder to find something that works for you. There are a million (well... maybe not quite that many) ways to deal with a failed engine and what works in one situation may not work in another.
There - that'll be $50.
Re: Forced Approach.
Find out how much altitude you loose in a 360 with the engine out (before the flight, preferably ).
-Find a field.
-Fly to the middle of that field at an altitude of (field elevation + altitude you loose in a 360) (the middle of that field becomes your aim point)
-Start a left/right hand turn into wind preferably.
-Once you get around 270 degrees of turn, start looking for your aimpoint.
-Once you make your aimpoint (midfield, ie: it doesn't move up or down in the canopy), dump full flaps and shift your aimpoint closer to the edge of the field.
-Land.
Don't forget: you can loose alitude easily by using more bank in the turn, sidesliping, dumping the flaps early, but you can't get it back. Don't be so eager to loose that altitude too early in the game.
).-Find a field.
-Fly to the middle of that field at an altitude of (field elevation + altitude you loose in a 360) (the middle of that field becomes your aim point)
-Start a left/right hand turn into wind preferably.
-Once you get around 270 degrees of turn, start looking for your aimpoint.
-Once you make your aimpoint (midfield, ie: it doesn't move up or down in the canopy), dump full flaps and shift your aimpoint closer to the edge of the field.
-Land.
Don't forget: you can loose alitude easily by using more bank in the turn, sidesliping, dumping the flaps early, but you can't get it back. Don't be so eager to loose that altitude too early in the game.
Going for the deck at corner
Re: Forced Approach.
I don't like it when a student says he has to get down!
If you have a fire, you have to get down, but otherwise you want to stay in the air as long as possible to give yourself as much time as possible.
So I don't always believe in best glide speed. Use best glide speed to get there and then best 'endurance' speed to stay in the air.
The normal approach speed is often less than the best glide...
By the way best glide is very different into a strong wind.
I like point to point straight legs with the aeroplane properly trimmed for the glide. Know how to trim that aeroplane so that you don't have to fly it while you've got other things to do.
Practice glide approaches from the end of the downwind when flying circuits, (ask ATC of course).
When you can make it to the runway (safely in from the threshold) note the height and distance you turn finals.
Key points are the keys.
Like the circuit, 1,000 feet AGL abeam the touchdown point and turning final at around 600 feet and a mile (60kts g/s, 600 fpm descent, no wind) will get you there in a Cessna, be higher/closer in the Cherokee, and you can be lower in a Katana/Eclipse.
Always checking the altitude high or low and making corrections.
Pilots rush this exercise, in a Cherokee this might be valid, but in a Cessna from 3,000' AGL you have up to five minutes.
Practice this exercise at home, forced landing a model aeroplane in your hand and going through the procedure, take your time!
I deliberately take a lot of time when I demonstrate this exercise, carb heat hot, glide, turn, cause checks, Mayday, Passenger brief, Emergency Checklist leading to securing the engine, flaps down, unlatch doors, master switch off...
A lot of this though is unreal as a benign engine failure is often due to fuel. Carb icing usually makes itself apparent and gets worse with carb heat application (then it gets better).
Magneto failure is dramatic if it starts firing the wrong plugs, turn it off and use the good one.
Mechanical failure has to be dealt with immediately. When the crankshaft broke I switched the mags off and pointed the nose up to see 40 KIAS as I pitched it over and the prop stopped, I wanted the engine to stay on the front of the aeroplane!
I've seen two mechanical failures in my life and one fuel starvation. The fuel starvation would have had a better outcome if the engines were feathered and secured immediately. Sometimes you don't have the luxury of time.
There's not enough emphasis of the facts that if a better field is crosswind it still can be chosen for its better surface, and if the Sun is low and landing out of it might be with a small tailwind this is often preferable as you can see where you are going with the Sun behind you.
As pilots if we consider all the possibilities were arm ourselves for the eventualities.
We arm ourselves every time we do the takeoff safety briefing.
If you have a fire, you have to get down, but otherwise you want to stay in the air as long as possible to give yourself as much time as possible.
So I don't always believe in best glide speed. Use best glide speed to get there and then best 'endurance' speed to stay in the air.
The normal approach speed is often less than the best glide...
By the way best glide is very different into a strong wind.
I like point to point straight legs with the aeroplane properly trimmed for the glide. Know how to trim that aeroplane so that you don't have to fly it while you've got other things to do.
Practice glide approaches from the end of the downwind when flying circuits, (ask ATC of course).
When you can make it to the runway (safely in from the threshold) note the height and distance you turn finals.
Key points are the keys.
Like the circuit, 1,000 feet AGL abeam the touchdown point and turning final at around 600 feet and a mile (60kts g/s, 600 fpm descent, no wind) will get you there in a Cessna, be higher/closer in the Cherokee, and you can be lower in a Katana/Eclipse.
Always checking the altitude high or low and making corrections.
Pilots rush this exercise, in a Cherokee this might be valid, but in a Cessna from 3,000' AGL you have up to five minutes.
Practice this exercise at home, forced landing a model aeroplane in your hand and going through the procedure, take your time!
I deliberately take a lot of time when I demonstrate this exercise, carb heat hot, glide, turn, cause checks, Mayday, Passenger brief, Emergency Checklist leading to securing the engine, flaps down, unlatch doors, master switch off...
A lot of this though is unreal as a benign engine failure is often due to fuel. Carb icing usually makes itself apparent and gets worse with carb heat application (then it gets better).
Magneto failure is dramatic if it starts firing the wrong plugs, turn it off and use the good one.
Mechanical failure has to be dealt with immediately. When the crankshaft broke I switched the mags off and pointed the nose up to see 40 KIAS as I pitched it over and the prop stopped, I wanted the engine to stay on the front of the aeroplane!
I've seen two mechanical failures in my life and one fuel starvation. The fuel starvation would have had a better outcome if the engines were feathered and secured immediately. Sometimes you don't have the luxury of time.
There's not enough emphasis of the facts that if a better field is crosswind it still can be chosen for its better surface, and if the Sun is low and landing out of it might be with a small tailwind this is often preferable as you can see where you are going with the Sun behind you.
As pilots if we consider all the possibilities were arm ourselves for the eventualities.
We arm ourselves every time we do the takeoff safety briefing.
Re: Forced Approach.
Learn how to agressively slip. Setup higher than you want to by by a considerable margin, many hundreds of feet or more, then just adjust the slip till your desired landing point stays fixed in the windscreen. If you are too low, back off the slip and drop the nose for more airspeed. If you are too high and already slipping more or less fully, slow down as much as you dare to increase the sink rate.
This has the added advantage of being about the only thing you can do if you have a major oil leak and the windscreen is obscured with oil. Its also an option in an engine fire since it keeps the smoke etc. slightly to the side of the plane instead of right infront of you.
The slip is infinitely more controllable than flaps and can be quickly increased/decreased as the situations changes. Save the flaps until you have the field clearly made and then transition off the slip to flaps.
This has the added advantage of being about the only thing you can do if you have a major oil leak and the windscreen is obscured with oil. Its also an option in an engine fire since it keeps the smoke etc. slightly to the side of the plane instead of right infront of you.
The slip is infinitely more controllable than flaps and can be quickly increased/decreased as the situations changes. Save the flaps until you have the field clearly made and then transition off the slip to flaps.
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Troubled_Coffee
- Rank 1
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Re: Forced Approach.
On the flight test your forced approach is graded into two categories: Cockpit procedures and Forced approach technique. For the PPL the examiner guide requires the examiner to pull the power no less than 3000' AGL. With this in mind try to fly your aircraft to that point of zero movement. I know that in a C-172, power off altitude loss is approximately 600 fpm giving at least 5 mins to execute the cockpit procedures. Try to rehearse the timing while flying to the POZM, and remember that if you get overloaded you can still pass the flight test if you make the field and at least attempt a restart, but will not pass should you pull off a perfect set of cockpit procedures and not make the field.
Re: Forced Approach.
One common error I found when I was instructing was that students would not watch the field.
They would look at it for a second, then their head would go back inside the airplane. Then look up again 15 secs later and then back inside. Snapshot pictures of where you are don't work.
Trim the airplane and watch the field as you fly the approach, (and do you checks etc with minimal time looking inside). This way you can see how the field is changing in relation to the aircraft. And by watching the relationship change you can make adjustments accordingly. You will not see yourself getting low or high if you are taking snapshot pictures of where the field is.
This method will work no matter what aircraft you fly. All you need is about 20 secs looking outside to see what the aircraft performance is like, then you can fly from there.
Key points etc are good, but use them as guides, not the be all end all.
I stressed looking outside when instructing in the DA C1 with a decent rate with engine failure of about 400 ft/min, and in the Zlins with a decent rate of about 1200 ft/min. Once you understand what to look for, it works.
BTD
They would look at it for a second, then their head would go back inside the airplane. Then look up again 15 secs later and then back inside. Snapshot pictures of where you are don't work.
Trim the airplane and watch the field as you fly the approach, (and do you checks etc with minimal time looking inside). This way you can see how the field is changing in relation to the aircraft. And by watching the relationship change you can make adjustments accordingly. You will not see yourself getting low or high if you are taking snapshot pictures of where the field is.
This method will work no matter what aircraft you fly. All you need is about 20 secs looking outside to see what the aircraft performance is like, then you can fly from there.
Key points etc are good, but use them as guides, not the be all end all.
I stressed looking outside when instructing in the DA C1 with a decent rate with engine failure of about 400 ft/min, and in the Zlins with a decent rate of about 1200 ft/min. Once you understand what to look for, it works.
BTD
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MorganAirCFI
- Rank 2
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- Joined: Fri Apr 25, 2008 1:32 pm
- Location: CYYC
- Contact:
Re: Forced Approach.
DO NOT USE FLAPS OR A FORWARD-SLIP as a standard forced approach.
Theses are last ditch efforts ONLY and should not be allowed during initial practice because they do not teach proper judgement. It really peeves me when students or instructors teach and practice this as routine. You are loosing altitude that you can never gain back if you misjudge your flaps or slip.
The problem steems from improper instruction during basic power-off descents which leads to improper judgement for forced approaches and the landing approaches.
Set up best glide. Look for the point on the ground that remains stationary. The ground above it expands upward, and below, downwards.
Look for this point gliding straight ahead first. This point is your glidepath, where you will impact the ground. You can save alot of frustration in the circuit and forced approaches if you hone this skill early on in descents in your first or second flight lesson. If not taught properly at the beginning, then bad habits develop which are very hard to break.
Set yourself up in a downwind to your field. Imagine this glide path squared off like a circuit to determine when to turn a base and final for your field. These are called key-points.
Turn Base at your key point, and look for this point straight ahead again and imagine it squared off to final.
If your glide path will cause you to overshoot your field at your first key point, you can move your next key point to turn final further away from the field. Effectively increasing the distance you need to glide to make the field. If you make a mistake you can always turn back to the field at this point to make the field.
If your glide path will cause you to undershoot your field at your first key point, you can move your key point to turn final closer to the field. Effectively decreasing the distance you need to glide to make the field. If you make a mistake you can always turn away from the field at this point to make the field.
Add flaps short final when assured, only to help with the softfield landing (or obstical).
This way you are effectively using the altitude you have, and leaves yourself options if you misjudge your glidepath. Imagine adding flaps or slipping then realising you are undershooting. You now can't fix it. You've lost all that altitude due to the increased drag that can never be regained.
It much better to use best glide speed which gives you the most time, judge your glidepath, and plan the approach in a circular or square pattern then monitoring your plan and adjusting as needed.
Look for that point that remains stationary.
Theses are last ditch efforts ONLY and should not be allowed during initial practice because they do not teach proper judgement. It really peeves me when students or instructors teach and practice this as routine. You are loosing altitude that you can never gain back if you misjudge your flaps or slip.
The problem steems from improper instruction during basic power-off descents which leads to improper judgement for forced approaches and the landing approaches.
Set up best glide. Look for the point on the ground that remains stationary. The ground above it expands upward, and below, downwards.
Look for this point gliding straight ahead first. This point is your glidepath, where you will impact the ground. You can save alot of frustration in the circuit and forced approaches if you hone this skill early on in descents in your first or second flight lesson. If not taught properly at the beginning, then bad habits develop which are very hard to break.
Set yourself up in a downwind to your field. Imagine this glide path squared off like a circuit to determine when to turn a base and final for your field. These are called key-points.
Turn Base at your key point, and look for this point straight ahead again and imagine it squared off to final.
If your glide path will cause you to overshoot your field at your first key point, you can move your next key point to turn final further away from the field. Effectively increasing the distance you need to glide to make the field. If you make a mistake you can always turn back to the field at this point to make the field.
If your glide path will cause you to undershoot your field at your first key point, you can move your key point to turn final closer to the field. Effectively decreasing the distance you need to glide to make the field. If you make a mistake you can always turn away from the field at this point to make the field.
Add flaps short final when assured, only to help with the softfield landing (or obstical).
This way you are effectively using the altitude you have, and leaves yourself options if you misjudge your glidepath. Imagine adding flaps or slipping then realising you are undershooting. You now can't fix it. You've lost all that altitude due to the increased drag that can never be regained.
It much better to use best glide speed which gives you the most time, judge your glidepath, and plan the approach in a circular or square pattern then monitoring your plan and adjusting as needed.
Look for that point that remains stationary.
Re: Forced Approach.
Huh?! I have performed thousands of power-off approachesDO NOT USE FLAPS OR A FORWARD-SLIP as a standard forced approach
in the Pitts from downwind (power goes to idle abeam the
numbers on downwind - remind you of a certain task on the
CPL flight test?) and if I do it right, I do not need to touch
the throttle again - I am not power dependent.
To do this, I like to stay just a bit high, and since I don't have
flaps, I routinely sideslip to lose a bit of energy after landing is
assured on final.
There is nothing wrong with sideslipping, or using flaps
if you have them, during a forced approach.
I personally prefer sideslips to flaps, because you can
instantly get rid of the drag in a slip by returning to
co-ordinated flight.
Most people don't like raising flaps on final, to try
to reduce drag, if they've applied too much flap -
it's a one-way trip.
Anyways. It's no wonder so many students
struggle with (and fail) the forced approach.
Re: Forced Approach.
I think it was fairly simple to see that what he was referring to was using flaps and sideslip to cover up piss poor technique and planning. As was what I read into this post.Quote:
DO NOT USE FLAPS OR A FORWARD-SLIP as a standard forced approach
Huh?! I have performed thousands of power-off approaches
in the Pitts from downwind (power goes to idle abeam the
numbers on downwind - remind you of a certain task on the
CPL flight test?) and if I do it right, I do not need to touch
the throttle again - I am not power dependent.
To do this, I like to stay just a bit high, and since I don't have
flaps, I routinely sideslip to lose a bit of energy after landing is
assured on final.
There is nothing wrong with sideslipping, or using flaps
if you have them, during a forced approach.
I personally prefer sideslips to flaps, because you can
instantly get rid of the drag in a slip by returning to
co-ordinated flight.
Most people don't like raising flaps on final, to try
to reduce drag, if they've applied too much flap -
it's a one-way trip.
Anyways. It's no wonder so many students
struggle with (and fail) the forced approach.
Not that you should bury the aircraft off the far end of the field you tried to land on because someone on avcanada told you not to use flaps or sideslips in a forced approach.Learn how to agressively slip. Setup higher than you want to by by a considerable margin, many hundreds of feet or more, then just adjust the slip till your desired landing point stays fixed in the windscreen. If you are too low, back off the slip and drop the nose for more airspeed. If you are too high and already slipping more or less fully, slow down as much as you dare to increase the sink rate.
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MorganAirCFI
- Rank 2
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- Joined: Fri Apr 25, 2008 1:32 pm
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Re: Forced Approach.
Exactly. The original post was asking how to practice forced approaches. Planning and judgment should be practiced over last ditch efforts such as diving bombing, slips, or dumping flaps. I would use a slips or flaps in a real scenario if I screwed things up, however its a poor thing to practice.BTD wrote:think it was fairly simple to see that what he was referring to was using flaps and sideslip to cover up piss poor technique and planning. As was what I read into this post.
Often students do things without thinking because an instructor didn't teach them how to think.
Re: Forced Approach.
If you make power off approaches your standard and concentrate on remembering the visual clues you see off such approaches, and then go a step further to challenging yourself to land on a particular point on the runway, and as written before, do this from the downwind then you will become better equipped to do the forced approach.
This is one of the things one should do in the 100 hour build up towards the CPL.
You can practice a forced approach on almost every flight if necessary.
This is one of the things one should do in the 100 hour build up towards the CPL.
You can practice a forced approach on almost every flight if necessary.
Re: Forced Approach.
Giveitago wrote:Oh Yeah, and cheat like crazy with sideslipping and flaps if you're to high.
And if you to low.....try "clearing" the engine one last time.
I strongly disagree, the purpose of the forced approach exercise is not to pass the flight test. All you would be doing would be cheating your self and saying "oh shit" when it actually happens. How about working on proper glide judgment and cockpit management instead of cheating? why would you be slipping ? because of poor glide judgment. Also, don't dump flaps right away, it's your last control to lose altitude faster; use it if necessary.
I call that bad advice Giveitago.
Re: Forced Approach.
Every forced approach is different, but here is the current
thinking on a simple procedure to teach students, to successfully
execute the forced approach.
Imagine the aircraft directly overhead the runway threshold,
pointing the same direction as the runway.
If the engine failed at that moment, let's say you initiated a
left (or right, doesn't matter) rate one turn. No steep turns
required.
Well, in the absence of strong winds, when you completed
360 degrees of a descending, power off, rate one turn, you
would be lined up with the runway again, ready for a perfect
touchdown.
Now let's say your aircraft loses 700 fpm. Rate one turn
is two minutes, that's 1400 feet. Add 200 feet for fudge,
so if you're 1600 feet AGL over a runway, pointing the
same direction as it, and you pull the power, and just
do a rate one turn, you will execute a perfect forced
approach
Food for thought.
FWIW that's what Transport is recommending we
instructors teach as a procedure for the forced approach.
Try it, it works!
thinking on a simple procedure to teach students, to successfully
execute the forced approach.
Imagine the aircraft directly overhead the runway threshold,
pointing the same direction as the runway.
If the engine failed at that moment, let's say you initiated a
left (or right, doesn't matter) rate one turn. No steep turns
required.
Well, in the absence of strong winds, when you completed
360 degrees of a descending, power off, rate one turn, you
would be lined up with the runway again, ready for a perfect
touchdown.
Now let's say your aircraft loses 700 fpm. Rate one turn
is two minutes, that's 1400 feet. Add 200 feet for fudge,
so if you're 1600 feet AGL over a runway, pointing the
same direction as it, and you pull the power, and just
do a rate one turn, you will execute a perfect forced
approach
Food for thought.
FWIW that's what Transport is recommending we
instructors teach as a procedure for the forced approach.
Try it, it works!
Re: Forced Approach.
Hedley wrote:Every forced approach is different, but here is the current
thinking on a simple procedure to teach students, to successfully
execute the forced approach.
Imagine the aircraft directly overhead the runway threshold,
pointing the same direction as the runway.
If the engine failed at that moment, let's say you initiated a
left (or right, doesn't matter) rate one turn. No steep turns
required.
Well, in the absence of strong winds, when you completed
360 degrees of a descending, power off, rate one turn, you
would be lined up with the runway again, ready for a perfect
touchdown.
Now let's say your aircraft loses 700 fpm. Rate one turn
is two minutes, that's 1400 feet. Add 200 feet for fudge,
so if you're 1600 feet AGL over a runway, pointing the
same direction as it, and you pull the power, and just
do a rate one turn, you will execute a perfect forced
approach
Food for thought.
FWIW that's what Transport is recommending we
instructors teach as a procedure for the forced approach.
Try it, it works!
Nicely said... what's with all these FTU's using the s turns? ... it's very inconvenient.
Re: Forced Approach.
There's one 'school' I know where this S turn business seems to be their favourite method judging by people who I have flown with from there.
The S turn idea is one for losing excess height and should not be the prime method of procedure.
Excess height should be used for time and for inspection. Radical height loss should be reserved for fires.
As for the two minute turn from above the field... Turning flight is not easy enough for the students to complete their emergency procedures.
For the circuit style PFL you can write a mathematical depiction of a forced landing procedure accounting for each turn's height loss in addition to the lengths of the straight flight segments.
In the past a student would fail using the high key/low key turn from overhead method as the examiner would argue "you turned away from the field".
Certainly with mechanical failure and the engine properly shut down the high key/low key method is good. But in the benign engine failure scenario we're expected to teach the procedure takes precidence and procedures require trimmed straight flight to accomplish.
The S turn idea is one for losing excess height and should not be the prime method of procedure.
Excess height should be used for time and for inspection. Radical height loss should be reserved for fires.
As for the two minute turn from above the field... Turning flight is not easy enough for the students to complete their emergency procedures.
For the circuit style PFL you can write a mathematical depiction of a forced landing procedure accounting for each turn's height loss in addition to the lengths of the straight flight segments.
In the past a student would fail using the high key/low key turn from overhead method as the examiner would argue "you turned away from the field".
Certainly with mechanical failure and the engine properly shut down the high key/low key method is good. But in the benign engine failure scenario we're expected to teach the procedure takes precidence and procedures require trimmed straight flight to accomplish.
Re: Forced Approach.
Turned away from the field? I think you're just using energy in the most efficient way to get down, safely and effectively. It's MUCH easier to assess your profile to the field and how the wind is affecting you by doing that than doind any other method. I was taught to do it that way, and never had to overshoot because I wasn't going to make the field.MichaelP wrote:In the past a student would fail using the high key/low key turn from overhead method as the examiner would argue "you turned away from the field".
You can do all the procedures before hand (try a restart, secure the engine) and once you get to high key, you can assess your profile and do the radio calls and brief the passengers. Arrive at low key, assess your Descent Angle with relation to the mid-field, Final Key, make sure you're making the mid-field, drop the flaps once your initial aim point (mid-field) doesn't move or moves down in your canopy, move your aim point closer to the edge of the field and land safely.MichaelP wrote:Certainly with mechanical failure and the engine properly shut down the high key/low key method is good. But in the benign engine failure scenario we're expected to teach the procedure takes precidence and procedures require trimmed straight flight to accomplish.
Personally, I'd take an airplane, see the rate of descend straight and level on the best glide speed, get a distance/altitude ratio, see how much altitude you loose in a 360 with 20-30 degrees bank. Take that, add 100 feet, that's your high key position. You should be at low key at 1/2 that altitude and at final key 1/4 of that altitude. With all that, and your altitude for the engine failure, you can figure out what's the fartest your field can be.
For example, if you loose 4400AGL in a 360 you are at 7000AGL feet when you loose your engine and you loose 1000 feet for every 2 miles you travel, your field can be 5 miles away and you'll make it (7000 - (4400+100) = 2500 feet * 2 miles/1000 feet = 5 miles). You get to your field 5 miles out, at 4500 feet AGL, initiate a turn into wind 20-30 degrees, keep it going, fine tune your bank to compensate for winds and roll out aligned with the field, drop the flaps when you make mid field, that will move your aim point way back.
To me, that's the safest way to do it. Plus, you have hard altitude that you know, if you're not there (for example in that case, 4400 feet at high key, 2200 feet at low key and 1100 feet at final key), you won't make the field. Also, if you're lower than one of the key before you initiate the manoever, you can fly to a low key position/final key position, aiming to be at the key's altitude and you'll be fine.
Going for the deck at corner
Re: Forced Approach.
E-Flyer wrote:Giveitago wrote:Oh Yeah, and cheat like crazy with sideslipping and flaps if you're to high.
And if you to low.....try "clearing" the engine one last time.
I strongly disagree, the purpose of the forced approach exercise is not to pass the flight test. All you would be doing would be cheating your self and saying "oh shit" when it actually happens. How about working on proper glide judgment and cockpit management instead of cheating? why would you be slipping ? because of poor glide judgment. Also, don't dump flaps right away, it's your last control to lose altitude faster; use it if necessary.
I call that bad advice Giveitago.
So apparently E-Flyer, the laughing smiley face and the fact that this quick post followed my actual "answer the question" post didn't convey the fact that this was indeed meant as humour......
Re: Forced Approach.
I was criticised for 'turning away from the field' 18 or so years ago in Canada...
I believe in joining the dots to make the field and that can just as well be a straight legs - circuit style approach to the field as a descending turn over the field.
Providing you know where you are in relation to the field you don't have to see it all of the time, and in the high key low key approach you may not necessarily see your field all the time.
This exercise should not be rushed, and unless the aeroplane is on fire it should not be rushed in an emergency.
In most cases you are not going to restart the engine...
If it's carb icing, or you forgot to change tanks then you want as much time in the air as possible to give yourself a chance.
In this respect I do not agree with using best glide speed unless the field is unlikely to be made unless best glide is used.
A slightly lower speed might mean more time in the air.
In gliding the K13 sailplane we'd hang around at 45 KIAS for minimum sink and use 55 KIAS best penetration/glide to get back to the airfield.
Having flown aircraft that have suffered from somewhat severe carb icing, and from fuel starvation, these things don't happen without warning.
You have to be extremely insensitive to suffer such problems in cruising flight.
Carb icing can kill your power on a go around, but now you are looking at a different thing altogether than the 3,000 feet AGL scenario. Likewise fuel starvation.
I've seen a student land a perfectly healthy Cessna 150 in a field with carb icing in the cool damp of an English winter. He had plenty of time to set himself up and land without much power left. Had he pulled the carb heat he wouldn't have had to do it at all!
I flew the aeroplane out again and that's another story.
In the DA20-C1 from 3,000 feet in the Pitt Lake practice area you can fly to Pitt Meadows Airport, 8 NM, do a circuit and land! Ridiculous.
In a Cherokee you need to stay very local! And yet the Cherokee engine failure scenario is more likely... Cessna pilots not realising there isn't a 'Both' in the Cherokee!
In the PA28 make sure the student does not follow the emergency procedures and actually turn the fuel off! Not easy to see from the right seat.
The most common engine failure is fuel starvation... A couple of pumps on the primer will be all you might get. Slipping to put fuel over the tank's outlet might give you a short burst but that's your lot.
Then there's commitment.
A Beagle Terrier ran out of fuel in England, made a good approach to the field and suddenly the engine came alive (slipping?) so the pilot added power to go around and with safety behind him the engine quit again.
The CAA published a recommendation that unless you are positive that power will continue it is safer to commit to the forced landing.
The best practice is done in your head, considering the possibilities and refering to accident reports for real life occurences.
I believe in joining the dots to make the field and that can just as well be a straight legs - circuit style approach to the field as a descending turn over the field.
Providing you know where you are in relation to the field you don't have to see it all of the time, and in the high key low key approach you may not necessarily see your field all the time.
This exercise should not be rushed, and unless the aeroplane is on fire it should not be rushed in an emergency.
In most cases you are not going to restart the engine...
If it's carb icing, or you forgot to change tanks then you want as much time in the air as possible to give yourself a chance.
In this respect I do not agree with using best glide speed unless the field is unlikely to be made unless best glide is used.
A slightly lower speed might mean more time in the air.
In gliding the K13 sailplane we'd hang around at 45 KIAS for minimum sink and use 55 KIAS best penetration/glide to get back to the airfield.
Having flown aircraft that have suffered from somewhat severe carb icing, and from fuel starvation, these things don't happen without warning.
You have to be extremely insensitive to suffer such problems in cruising flight.
Carb icing can kill your power on a go around, but now you are looking at a different thing altogether than the 3,000 feet AGL scenario. Likewise fuel starvation.
I've seen a student land a perfectly healthy Cessna 150 in a field with carb icing in the cool damp of an English winter. He had plenty of time to set himself up and land without much power left. Had he pulled the carb heat he wouldn't have had to do it at all!
I flew the aeroplane out again and that's another story.
In the DA20-C1 from 3,000 feet in the Pitt Lake practice area you can fly to Pitt Meadows Airport, 8 NM, do a circuit and land! Ridiculous.
In a Cherokee you need to stay very local! And yet the Cherokee engine failure scenario is more likely... Cessna pilots not realising there isn't a 'Both' in the Cherokee!
In the PA28 make sure the student does not follow the emergency procedures and actually turn the fuel off! Not easy to see from the right seat.
The most common engine failure is fuel starvation... A couple of pumps on the primer will be all you might get. Slipping to put fuel over the tank's outlet might give you a short burst but that's your lot.
Then there's commitment.
A Beagle Terrier ran out of fuel in England, made a good approach to the field and suddenly the engine came alive (slipping?) so the pilot added power to go around and with safety behind him the engine quit again.
The CAA published a recommendation that unless you are positive that power will continue it is safer to commit to the forced landing.
The best practice is done in your head, considering the possibilities and refering to accident reports for real life occurences.
-
jetflightinstructor
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- Joined: Thu Mar 06, 2008 5:13 am
Re: Forced Approach.
What about a glider licence before the PPL? You can count 10 glider hours towards the CPL (or more I forgot), and very valuable experience. Forced landing would be natural. And you will get your PPL within 45 hours... The cheapest and best way is not always the straight one...
Re: Forced Approach.
I have the 'A' certificate for one solo flight in a Sedburg off a winch launch.
Once in every few years I get the chance to do an aerotow to see if I can still do one in a Blanik.
I agree, some gliding is good for a pilot.
We should only turn down experiences when they really really scare us... Like parachuting and perhaps auto-gyro/gyroplanes of the Benson style... I've seen them crash.
Once in every few years I get the chance to do an aerotow to see if I can still do one in a Blanik.
I agree, some gliding is good for a pilot.
We should only turn down experiences when they really really scare us... Like parachuting
and perhaps auto-gyro/gyroplanes of the Benson style... I've seen them crash.Re: Forced Approach.
Giveitago wrote:E-Flyer wrote:Giveitago wrote:Oh Yeah, and cheat like crazy with sideslipping and flaps if you're to high.
And if you to low.....try "clearing" the engine one last time.
I strongly disagree, the purpose of the forced approach exercise is not to pass the flight test. All you would be doing would be cheating your self and saying "oh shit" when it actually happens. How about working on proper glide judgment and cockpit management instead of cheating? why would you be slipping ? because of poor glide judgment. Also, don't dump flaps right away, it's your last control to lose altitude faster; use it if necessary.
I call that bad advice Giveitago.
So apparently E-Flyer, the laughing smiley face and the fact that this quick post followed my actual "answer the question" post didn't convey the fact that this was indeed meant as humour......
I don't think humor belongs when it tackles a prime deficiency in many applicants flight tests these days. It makes it seem like the other way is also a good method, which it is not.
I am very well aware of what you wrote in the answer to the question. I just thought it would be proper to correct an assumption that many students have, "oh i'll just slip it down."
Re: Forced Approach.
All these complicated circuit points and altitudes are ridiculous and I'll put odds down that you won't remember any of them in an emergency. How about we do it the (very) easy way.
You have one waypoint. It's one mile back from your touchdown point. Do figure eights on it until you are ready to turn final.
It's so easy this way. It makes it even easier to make all turns INTO the field, just keep figure eighting on it until you should turn. When should you turn? Well you should be able to SEE when, that's what the training is for. But in a 172, 600 or 700 feet above ground at 1 mile final should be about right. Depends on the winds (and please dont approach downwind!) Get your flaps in to get even lower. I know it's not a pass/fail item but you should have all the flaps in for touchdown. You can get slower on touchdown with flaps in and that means a crash won't hurt as bad and you don't need as much field. But let me reiterate.
You have one waypoint. It's one mile back from your touchdown point. Do figure eights on it until you are ready to turn final.
Here is a picture.
FIELD--8
You have one waypoint. It's one mile back from your touchdown point. Do figure eights on it until you are ready to turn final.
It's so easy this way. It makes it even easier to make all turns INTO the field, just keep figure eighting on it until you should turn. When should you turn? Well you should be able to SEE when, that's what the training is for. But in a 172, 600 or 700 feet above ground at 1 mile final should be about right. Depends on the winds (and please dont approach downwind!) Get your flaps in to get even lower. I know it's not a pass/fail item but you should have all the flaps in for touchdown. You can get slower on touchdown with flaps in and that means a crash won't hurt as bad and you don't need as much field. But let me reiterate.
You have one waypoint. It's one mile back from your touchdown point. Do figure eights on it until you are ready to turn final.
Here is a picture.
FIELD--8
