Gusty conditions on approach
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I'll take your point about 60 kts Pace, but as a Cub lands at less than 35 I'm sure you can see that whilst flying in 50kts of wind is possible (backwards is particular fun if you're not going anywhere!) there is a bit of a problem in the landing phase.
It can be done but usually involves getting someone on the ground to help or somewhat unusual measures.
I've landed into the lee of some trees at a strip, into the lee of a large hangar at an airfield, and had my passenger hanging on for all she was worth to a wingtip at Newcastle. Essentially if the wind gets over 30 kts these aircraft can be picked up and rolled into a ball.
It can be done but usually involves getting someone on the ground to help or somewhat unusual measures.
I've landed into the lee of some trees at a strip, into the lee of a large hangar at an airfield, and had my passenger hanging on for all she was worth to a wingtip at Newcastle. Essentially if the wind gets over 30 kts these aircraft can be picked up and rolled into a ball.
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Gasax
I take your point but the same principals hold good albeit on a much lower scale with light aircraft.
I would much rather carry speed in hand in such conditions and get rid of the speed when I know I am in much more stable air nearer the ground.
I can use the energy available from that extra speed if need be. No extra speed and I only have my engines to save me. If you have experienced half serious windshear you will know you wont want to rely on the engine alone especially when you are thrown onto the back of the drag curve by the shear and lack of speed
Pace
I take your point but the same principals hold good albeit on a much lower scale with light aircraft.
I would much rather carry speed in hand in such conditions and get rid of the speed when I know I am in much more stable air nearer the ground.
I can use the energy available from that extra speed if need be. No extra speed and I only have my engines to save me. If you have experienced half serious windshear you will know you wont want to rely on the engine alone especially when you are thrown onto the back of the drag curve by the shear and lack of speed
Pace
30% margin is a lot...
...and 'planes don't fall out of the sky at stall speed.
If your cub Vs is 38mph, then your approach speed is 1.3x or ~50mph. This gives you a margin of 10kts, which if you use the 1/2 gust factor rule, means you've got wind gusting some 20kts - not exactly unchallenging conditions.
Even if the IAS drops suddenly, you've still got the stick and the throttle to give you some more - probably more than quick enough to recover you a safe margin again if you've got your mind on the job.
If you're flying directly into 10G30 and add half the gust, then you'll arrive with 2.5 times the kinetic energy than you would at your normal Vapp.
Just my zwei pfennigs
A
If your cub Vs is 38mph, then your approach speed is 1.3x or ~50mph. This gives you a margin of 10kts, which if you use the 1/2 gust factor rule, means you've got wind gusting some 20kts - not exactly unchallenging conditions.
Even if the IAS drops suddenly, you've still got the stick and the throttle to give you some more - probably more than quick enough to recover you a safe margin again if you've got your mind on the job.
If you're flying directly into 10G30 and add half the gust, then you'll arrive with 2.5 times the kinetic energy than you would at your normal Vapp.
Just my zwei pfennigs
A
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Even if the IAS drops suddenly, you've still got the stick and the throttle to give you some more - probably more than quick enough to recover you a safe margin again if you've got your mind on the job.
Andy RR,
I agree.
That is exactly how I have been flying to date.
My original question was caused by reading somewhere that I should be adding significant airspeed at the time and place when I don't want it.
And I think you,Beagle and others have answered it for me.
I might try some approaches at 60 mph in calm conditions and see how I get on,because in gusts I could be approaching at over 60mph as some recommend,the wind drops right off, then find I'm on the threshold at around 5-10 mph more airspeed than normal,and possible significantl increase in ground-speed.
I'll try when it's low or zero wind and see how far I float before touching down, then if it looks dodgy go around,might have to go around before touching down if it looks tight.
Lister
Andy RR,
I agree.
That is exactly how I have been flying to date.
My original question was caused by reading somewhere that I should be adding significant airspeed at the time and place when I don't want it.
And I think you,Beagle and others have answered it for me.
I might try some approaches at 60 mph in calm conditions and see how I get on,because in gusts I could be approaching at over 60mph as some recommend,the wind drops right off, then find I'm on the threshold at around 5-10 mph more airspeed than normal,and possible significantl increase in ground-speed.
I'll try when it's low or zero wind and see how far I float before touching down, then if it looks dodgy go around,might have to go around before touching down if it looks tight.
Lister
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Lister
I have deleted my response. In mild winds you should not come to too much harm using those techniques so enjoy. If you ever get up with heavy winds and windshear thats a different matter. Take care and safe flying
Pace
I have deleted my response. In mild winds you should not come to too much harm using those techniques so enjoy. If you ever get up with heavy winds and windshear thats a different matter. Take care and safe flying
Pace
Last edited by Pace; 3rd Sep 2009 at 17:15.
Lister, my advice would be to leave test piloting to those who get paid for it! Just fly the Cub the way you're doing and you'll be fine.
stick only your little toe in the water, if you must.
If you're troubled by the possibility of severe wind-shear occuring, presumably caused by topographical features, then there's nothing wrong with doing an approach and go-around at an elevated approach speed to check out what the ASI does
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Hello, Lister Noble.....
Sounds like you manage your flapless Cub very well at your local field. It is the local knowlege that probably keeps you safe.
I have lots of hours in my Super Cub, lots of takeoffs (tugging) and lots of landings, and there comes a point when I say No Way Jose! A headwind is all very well, just float down and sit there until help arrives, to walk with the wing back to the hangar. Or take a heavy passenger, that helps you stay on the ground. It's the gusts that are scary, especially the ones from unexpected directions.
Twice I have suffered the embarassment of a ground loop; one time a gust from an earth bank caused an uncommanded fancy maneuver. Fortunately without hitting anything. The second occasion was at a small "International Airport" that shall remain nameless, number 1 on approach with a 737 as number 2. And rolling out got clobbered by a gust from 90 degrees, ended up stuck in the mud with the tail in the air, while the 737 had to go around. And around. Only luck prevented damage. It just ain't worth it, in my opinion. You don't want to bend it, really.
Sounds like you manage your flapless Cub very well at your local field. It is the local knowlege that probably keeps you safe.
I have lots of hours in my Super Cub, lots of takeoffs (tugging) and lots of landings, and there comes a point when I say No Way Jose! A headwind is all very well, just float down and sit there until help arrives, to walk with the wing back to the hangar. Or take a heavy passenger, that helps you stay on the ground. It's the gusts that are scary, especially the ones from unexpected directions.
Twice I have suffered the embarassment of a ground loop; one time a gust from an earth bank caused an uncommanded fancy maneuver. Fortunately without hitting anything. The second occasion was at a small "International Airport" that shall remain nameless, number 1 on approach with a 737 as number 2. And rolling out got clobbered by a gust from 90 degrees, ended up stuck in the mud with the tail in the air, while the 737 had to go around. And around. Only luck prevented damage. It just ain't worth it, in my opinion. You don't want to bend it, really.
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BEagle wrote in big red letters.."The only speeds to use are those in the POH!!!"
Lots of permit aircraft, especially home builts do not have a POH !!!
So, what do I do then?
Lots of permit aircraft, especially home builts do not have a POH !!!
So, what do I do then?
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Hatz,I never knew that,but surely they have test flights before being certificated,and that would give all the required speeds etc?
Lister
Lister
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Thats the whole point they are Not certified aircraft so they are not certificated.
As there are so many variables left to the discretion of the builder,no two are the same, hence stall speeds etc. vary.
edited..
Chox how can your europa have a definitive POH when choices of engines etc ( and therefor all up weight/C of G etc ) will have a profound effect on stall speed and therefor approach speed ?
My point is the previos post made a bold statement in huge red letters that was blatently rubbish.
There are quite a few two seat plans built aircraft currently flying that are restricted to one seat because they were built too heavy in the first place.The landing speeds will vary enourmously.
I own 4 permit to fly aircraft, none of them have a POH so by the previous poster's reckoning I can not fly any of them!
As there are so many variables left to the discretion of the builder,no two are the same, hence stall speeds etc. vary.
edited..
Chox how can your europa have a definitive POH when choices of engines etc ( and therefor all up weight/C of G etc ) will have a profound effect on stall speed and therefor approach speed ?
My point is the previos post made a bold statement in huge red letters that was blatently rubbish.
There are quite a few two seat plans built aircraft currently flying that are restricted to one seat because they were built too heavy in the first place.The landing speeds will vary enourmously.
I own 4 permit to fly aircraft, none of them have a POH so by the previous poster's reckoning I can not fly any of them!
Last edited by hatzflyer; 4th Sep 2009 at 11:33.
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Sorry Hatz,I didn't know that.
So are your aircraft flying on a permit like the Cub ie LAA?
Just interested.
Can anyone build an aircraft to plan and alter what he likes within aerodynamic reason?
There must be some rules to follow,or maybe not?.
I know in the USA they have various sorts,like sports and experimental,is that the same here?
I don't know much ,do I?
Lister
So are your aircraft flying on a permit like the Cub ie LAA?
Just interested.
Can anyone build an aircraft to plan and alter what he likes within aerodynamic reason?
There must be some rules to follow,or maybe not?.
I know in the USA they have various sorts,like sports and experimental,is that the same here?
I don't know much ,do I?
Lister
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Hatz, you are being a little economical with the truth there.
The approach speeds, stall speeds etc for every permit aircraft are tested and recorded. I do enough test flying for the LAA to confirm that. They may not have a POH but the figures are known and it is down to a good pilot to fly those speeds. When I am doing an initial test flight the first thing I look for is the manufacturers claimed numbers and go off and test as against those. It is rare to find a kit these days that is much outside the manufacturers numbers. I flew a CZW Sportscruiser last week for it's test flight for initial permit issue and the numbers were within a kt or so of the manufacturers claimed figures.
The approach speeds, stall speeds etc for every permit aircraft are tested and recorded. I do enough test flying for the LAA to confirm that. They may not have a POH but the figures are known and it is down to a good pilot to fly those speeds. When I am doing an initial test flight the first thing I look for is the manufacturers claimed numbers and go off and test as against those. It is rare to find a kit these days that is much outside the manufacturers numbers. I flew a CZW Sportscruiser last week for it's test flight for initial permit issue and the numbers were within a kt or so of the manufacturers claimed figures.
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Lister,No need to be sorry, you've done nothing wrong!
I'm only over the hedge, pop over for a chat (tibenham).PM me.
For the purpose of answering your question publically..here goes.
On a LAA permit, previously PFA, many designs were plans built and the engine installation was often not included.
Provided it met certain criteria it was up to the inspector to clear it.
More modern designs are often sold as kits, but very few include engines although this is changing and now becoming normal.
The Europa (as mentioned) was sold as a kit of airframe parts only.Older kits had foam core wings which were covered in fibreglass and sanded by the buider (in simple terms). this can lead to all sorts of differances in handling caused by weight, imbalance,differences in profile etc etc.
Later kits had a better system.
Couple this to the fact that people have fitted Jabaru, volkswagen(never seen one fly), saburu with/without reduction drive, and rotax of varing horsepower ...engines and it becomes easy to see how performance will vary very much from one to another and so will handling.
Add to the mis-mash ground adjustable props, fixed pitch props, constant speed props and simple variable pitch props.
Throw in a little mixture of monowheel, trike, or tailwheel undercarriage and you can soon begin to understand that the manufacturer of the original kit has very little control over the end product.As a result they cannot offer a POH!!!
edited
Bose.
Ok it would take all day to explain every avenue of every topic, but you are only talking about releively new designs
Ok Tell me where to get a POH for my jodel D9,or my Nipper,or my Moni, or for that matter my vans rv4 fitted with a one off engine installation.
I'm only over the hedge, pop over for a chat (tibenham).PM me.
For the purpose of answering your question publically..here goes.
On a LAA permit, previously PFA, many designs were plans built and the engine installation was often not included.
Provided it met certain criteria it was up to the inspector to clear it.
More modern designs are often sold as kits, but very few include engines although this is changing and now becoming normal.
The Europa (as mentioned) was sold as a kit of airframe parts only.Older kits had foam core wings which were covered in fibreglass and sanded by the buider (in simple terms). this can lead to all sorts of differances in handling caused by weight, imbalance,differences in profile etc etc.
Later kits had a better system.
Couple this to the fact that people have fitted Jabaru, volkswagen(never seen one fly), saburu with/without reduction drive, and rotax of varing horsepower ...engines and it becomes easy to see how performance will vary very much from one to another and so will handling.
Add to the mis-mash ground adjustable props, fixed pitch props, constant speed props and simple variable pitch props.
Throw in a little mixture of monowheel, trike, or tailwheel undercarriage and you can soon begin to understand that the manufacturer of the original kit has very little control over the end product.As a result they cannot offer a POH!!!
edited
Bose.
Ok it would take all day to explain every avenue of every topic, but you are only talking about releively new designs
Ok Tell me where to get a POH for my jodel D9,or my Nipper,or my Moni, or for that matter my vans rv4 fitted with a one off engine installation.
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Which is all true. But for the sake of this argument it is about the stall speed and the 'usual' approach speed and then suitable factors.
The Cubs original POH is possibly as irrelevent as most permit aircraft as it was done in a new aircraft, at minimum weight with a 'hotshot' test pilot. It will not meet the original POH figures. (which was partially why in simpler days they could transfer to a permit!!).
I presently fly an aircraft which can 'approach' at anything between 53 and 75 kts. 53 represents the 'guidance' figure of 1.3 x Vs with flaps. At that speed it trims out and quietly flies itself into ground effect.
On a gusty day apart from not being as stable, it gets closer to the stall than I prefer (only 12 kts margin at 53) and has less gust penetration ability, so less flap - the corresponding speed increase and then the plus 5 usually cover it up to about 30 odd knots and means flying at 65-ish.
As it is a trike I would be happy flying in a fair bit more wind and adding Pace's number of half the gust. But even a trike wil need help on the ground manoeurving in those winds.
The Cubs original POH is possibly as irrelevent as most permit aircraft as it was done in a new aircraft, at minimum weight with a 'hotshot' test pilot. It will not meet the original POH figures. (which was partially why in simpler days they could transfer to a permit!!).
I presently fly an aircraft which can 'approach' at anything between 53 and 75 kts. 53 represents the 'guidance' figure of 1.3 x Vs with flaps. At that speed it trims out and quietly flies itself into ground effect.
On a gusty day apart from not being as stable, it gets closer to the stall than I prefer (only 12 kts margin at 53) and has less gust penetration ability, so less flap - the corresponding speed increase and then the plus 5 usually cover it up to about 30 odd knots and means flying at 65-ish.
As it is a trike I would be happy flying in a fair bit more wind and adding Pace's number of half the gust. But even a trike wil need help on the ground manoeurving in those winds.
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Ok Tell me where to get a POH for my jodel D9,or my Nipper,or my Moni, or for that matter my vans rv4 fitted with a one off engine installation.
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I'm not the one playing on words..BEagle wrote THE ONLY SPEEDS TO USE ARE THOSE IN THE POH!!!
My question to him was I have no POH,what do I do now?
The test pilot that flew my jodel back in the sixties may have made some notes but have long since been lost. I bought it as a non runner and had to do the first flights based purely on experience and intuition.
There was no POH, there still is no POH. same for the other 3.
The point being that there is no one size fits all in aviation,especially true of homebuilts.
My question to him was I have no POH,what do I do now?
The test pilot that flew my jodel back in the sixties may have made some notes but have long since been lost. I bought it as a non runner and had to do the first flights based purely on experience and intuition.
There was no POH, there still is no POH. same for the other 3.
The point being that there is no one size fits all in aviation,especially true of homebuilts.
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Chox how can your europa have a definitive POH when choices of engines etc ( and therefor all up weight/C of G etc ) will have a profound effect on stall speed and therefor approach speed ?
I regularly (about every three months) check the recorded stall speeds against current performance - they are still same as initally recorded (within the accuracy of my ASI) and these are the speeds I use for calculating approach speed (1.3 times stall speed in landing configuration - full flap, prop in climb mode)