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Lister Noble
2nd Sep 2009, 15:19
Approach/landing speed in gusty conditions.
I have been flying the L4-Cub (65hp) in some quite gusty conditions recently, without incident and sticking to the speeds on the POH, which I understand allows for gusty conditions.
Approach speed 55mph, over the threshold 50mph, stall 35-38mph depending on load.
Some people say add 30% to approach speed, other experienced pilots say definitely not.
Adding 30% to approach is going to give me over 70 mph, which is nearly flat out!
Others say add half the gust speed,although how you judge this from a windsock on an unmanned strip I don't know,anyway say it was headwind 15mph gusting 30, adding half the gust would add over 7 mph to approach.
I would appreciate some thought from experienced pilots flying this sort of aircraft.
Lister:)
I tried search with a lot of results but no real answer.

Choxolate
2nd Sep 2009, 15:28
A "non gusty" approach is normally at 1.3 times stall - which would be 1.3 X 38 in the figures you gave - say 50 mph (assuming the 38 mph is in landing config)

With gusting I would add 5 knots (6 mph) to that (to be exact you need to know the headwind component of the gusts and apply a little formula to calculate the required "overspeed") but 6 mph should be OK for gusts of up to 10 - 12 knots over the steady headwind component.

Arclite01
2nd Sep 2009, 16:06
Hi Lister

+5Kts for the wife and kids, make sure you have enough room to land down the strip - with increased control comes increased penetration - especially an issue coming in from the North End.

cheers

Arc

Pace
2nd Sep 2009, 16:24
Lister

It is not just the suface wind gusts which are relevant it is also the approach wind gusts which have to be taken into consideration.

On your approach where the winds may be higher keep an eye on the IAS and the + AND - on your ref speed.

It maybe on the approach that you need to keep a much higher speed reducing towards the threshold as the winds reduce.

To fly down an approach at 1.3 times your stall speed plus half your gust speed maybe asking for trouble. On gusty days with windshear dont presume you are safe at 3 miles out using those figures.

As for landing distance remember its your touchdown speed which is relevant so whether the wind is down the runway or 90 degrees across is an important factor.

In those conditions also dont hold off but get used to putting it down on landing.
I am not a taildragger pilot so the actual touchdown in those conditions maybe better advised by an experienced taildragger pilot.

Pace

Lister Noble
2nd Sep 2009, 16:49
Thanks Arclite,you know this Cub very well;)
Sorry mate,it's yours again if ever I can't fly it.:)
5mph sounds about right,any more and I'll be through the hangars or Bob's house.
I'm OK on cross winds,but will not attempt gusty crosswinds where the gust component is much more than the steady airstream limit for the aircraft I'm flying.
For those not conversant,the Cub has no special landing configuration,as it has no flaps,retractable,or anything much else for that matter
(when I had a glider lesson locally the instructor reckoned I must be very used to all the instruments,I told him the glider had about twice as many as the Cub!)
Pace,thank you, I'm aware that the wind speed increases and changes direction with height,it's what happens nearer the ground that concerns me,especially as both approaches are over obstructions,such as trees,houses and hangars,and can be quite turbulent in strong winds.
I do keep an eye on the IAS until over the threshold,then I'm mostly looking out and landing
Lister:)

Pace
2nd Sep 2009, 20:52
Pace,thank you, I'm aware that the wind speed increases and changes direction with height

Lister

Thought you were aware but used this thread to highlight flying in gusty, windshear conditions. I have flown with pilots who use the surface wind gust speeds for their approach speed from maybe 2500 feet and 6 miles out with ASI fluctuations of 10-15 kts in up and down air currents. SCARY.

Pace

Captain Stable
3rd Sep 2009, 00:44
Lister, it's a long time since I flew a taildragger, and mostly it was rather heavier ones than your Cub.

Choxolate gives some good numbers. To add a little to that, recheck your POH. It should tell you fairly explicitly the limits for the gusts allowed for. Beyond that, I would (personally) increase my IAS by all the increase in gust factor.

Say the POH allows for gusts up to 15 kts. If the wind is gusting 20 kts, I would add a further 5 kts on top of what you've already added.

BEagle
3rd Sep 2009, 06:51
All this 'add 5 knots for the wife and kids' and 'add 1/3 gust' is utterly irrelevant in a light aircraft.

The 'gust factor' addition is only relevant to large aircraft (such as airliners) with high inertia which do not react to gusts as quickly as light, low inertia aircraft such as your Cub.

If you increase your approach speed as some have, quite wrongly, suggested, it will make control in the flare more difficult as you will be significantly out of trim before landing.

THE ONLY SPEEDS TO USE ARE THOSE IN THE POH!!

Some years ago, the club where I flew used a 'threshold' speed of 65 KIAS for the PA28 Warrior and insisted on an extra 5 knots with 3 or more PoB, PLUS 1/3 of the W/V if above 15 knots. So with a fresh 21 knot wind and 3 on board, people were using 77 KIAS as the 'threshold speed' and adding a further 10 knots for the approach - approaching as 87 KIAS! All this meant was that the aircraft would bounce all over the place, then, in the flare some 30 knots above the touchdown speed, they couldn't maintain finesse of control and would either thump it down on the nosewheel or land in an uncontrolled manner after ballooning.

Research showed that the approach speed is 63 KIAS at max AUW - we used 65 simply because it was easier to keep the AI needle midway between the 60 and 70 marks. Thanks to the efforts of the chaps who now run OnTrack Aviation, we rewrote the checklist deleting any reference to 'threshold' or 'reference' speeds, deleting any 'add 5 knots' or 'add 1/3 of the wind' nonsense - and never had another damaged nosewheel or heavy landing ever again.

This is even more vital in a taildragger; you do not want to be waffling about well above touchdown speed near the ground whilst the IAS decays and the aircraft goes out of trim. Just stick to the POH values and don't listen to ex-airliner drivers who import irrelevant ideas into the light aircraft world. Scan touch down point - speed - touchdown point - speed continuously during the approach and if the speed is incorrect, make a small power corrective adjustment whilst maintaining the selected touchdown point.

Piper.Classique
3rd Sep 2009, 07:10
Hi there
I fly a 150 cub, which is a lot heavier, also three axis microlights which come in a bit lighter, so my opinion may have some small value. In the cub I approach in still air at 45 knots, 40 with a trickle of power for short field, but my cub has great big flaps that go down to sixty degrees. Flaps up I use 50 knots. Up to five knots on the ground I don't add anything to that. Then I add half the steady wind plus all of the gusts, so if there was a fifteen knot wind gusting twenty that would be half of fifteen plus all of the five knot diference, less the five knots that I reckon is already accounted for, which is seven knots after I have done the sums. So five knots without the maths sounds about right, a trickle more if it's really rough. :ok: The POH is sodall use btw. It might be relevant to the aircraft as built in 1953, but as it now has different wings and a different engine it doesn't really apply any more. Beagle has a point about low inertia aircraft, but remember the speed can also decrease very rapidly in a shear or downgust, and a small increment of extra speed is handy to allow the pilot's reaction time to be less than instantaneous. In a gusting crosswind I use a wing down tail up landing with half flap, which seems to give good aileron reponse and still quite a lot of extra drag to shorten the run. It's a lot easier than trying to three point it while kicking off the drift and gives good rudder control through more of the rollout if the tail is up. Like you I fly without the dubious benefit of ATC, so have to judge from the windsock. I reckon if it is shredding itself to bits there is probably too much wind of any sort ;) I do have the pleasure of a huge grass runway 80m wide and 700m long, a fair bit of curlover on approach on 05 in a brisk wind however. How small is your strip?

Oh, and my approach speed in the microlight (skyranger nosedragger) is the same as for the cub, but it bleeds off a lot quicker in the hold-off.

Lister Noble
3rd Sep 2009, 07:10
That is exactly what I have been doing,looking at AIS,strip,AIS strip, and it has worked well in quite strong gusty conditions,and of course I use the same when it is smooth.
The reason I asked the question is that I've recently been reading some handling stuff and wondered if I was doing it OK.
When I was learning (still am,very much:)) my CFI was a very experienced pilot and I'm sure he never mentioned all this about increasing airspeed in rough conditions.
Lister

Pace
3rd Sep 2009, 07:12
we rewrote the checklist deleting any reference to 'threshold' or 'reference' speeds, deleting any 'add 5 knots' or 'add 1/3 of the wind' nonsense - and never had another damaged nosewheel or heavy landing ever again.

Beagle

I am Gobsmacked I hope you also wrote "not to be flown in windy condtions", using that checklist.

What relevance does your approach speed have to your touchdown speed anyway?
Why if you are carrying plus 30 kts above your ref speed on approach does that mean you are doing so at the threshold?

The 'gust factor' addition is only relevant to large aircraft (such as airliners) with high inertia which do not react to gusts as quickly as light, low inertia aircraft such as your Cub.

New to me. In a windshear are light aircraft immune to sudden and abrupt sink? How do you counteract that with not enough airspeed over the stall?

Pace

Lister Noble
3rd Sep 2009, 07:16
Runway grass 600 metres long,hangars one end,ditch other end,also not very wide but not sure of exact figure,crop/hedge one side,crops only other side.
Lister

BEagle
3rd Sep 2009, 07:26
Firstly, if the approach speed is way too high, the rate of decay even at idle power will mean that the average pilot won't be able to control the aircraft with sufficient finesse during the flare. The aircraft will float and wander in an uncontrolled manner.

Ignore airliner-driver rubbish about increasing approach speed in light aircraft in gusty conditions, Lister, to my mind it's clear that you're flying the aircraft in a sound, safe manner and that your old CFI's experience and wisdom was 100% correct.

gasax
3rd Sep 2009, 07:40
I've a reasonable amount of experience in light taildraggers (350 odd hrs). Adding the gust speed and various increments of 5 knots concerns me somewhat.

A number of the aircraft I've flown have flap limiting speeds which are well below the likely end number resulting from this arithmetic, add in real gustiness and damage is a real possibility.

In an L4/J3 this is not a concern, but carrying too much energy into ground effect can be. Yes I do add some speed when it gets gusty (not when it is windy unless it is a strong crosswind) 5 knots or so will allow you a little margin when you fly into the 'hole' behind the gust front.

A light aircraft like a L4 will not fall out of the sky when the apparent wind drops, the 5 knots is plenty to give you that bit more energy to fly through. (different if you fly into an area of curl over turbulence - only ground effect will save you there).

Aim for a wheeler landing and once the wheels touch gently hold them on. If the wind is gusting across this is your last opportunity to see if it is sensible to land (yes I know you're on the ground - but you still have enough energy to open the throttle and just lift off). If you can keep straight without using the brakes it is generally safe enough to close the throttle and commit to 'landing'. Keep the tail up and be ready with the brakes. As the tail falls, you will probably need the brakes (the rudder's effectiveness reduces as the speed falls, when you can no longer hold the tail up, the rudder will be equally ineffective so this movewment is a good signal) and one good brake application is generally enough. If you arrive with more speed then you can become very dependent on the brakes - not a good idea in any taidragger let alone with a Cub's bladders.

Then you just have the challenge of taxiing to where ever you need to go - which may be more difficult!

I have a vague recollection that 'Stick and Rudder' has some very good illustrations and descriptions.

Lister Noble
3rd Sep 2009, 10:16
gasax,I've got Stick and Rudder so will have a read through.
Lister:)
When I get back from the dentist:{

Pace
3rd Sep 2009, 10:35
5 knots or so will allow you a little margin when you fly into the 'hole' behind the gust front.

Gasax I am not a taildragger pilot but apart from the differences in placing the aircraft on the ground fail to understand some of tnhe reasoning placed in this thread.

I can only presume that pilots of light taildraggers only fly in mild wind and gust conditions. there is nothing wrong with that as flying for pleasure doesnt mean going off in heavy wind conditions.

There are pilots who fly for pleasure and pilots who must. There is a big difference between flying in winds of 10 kts gusting 15/20 kts where you can add a ballpark figure of 5 kts and flying in winds of 25kts gusting 50 kts or greater and dealing with the windshear in those situations.

I would love to hear from a taildragger pilot who must. A heavier taildragger like a DC3 in heavy winds?

Beagle mentions large aircraft and inertia. true as are jets engines spooling time and the need to pre judge thrust increases.

But a large ship ploughs through waves. A small boat rides with every ripple
Low powered aircraft can be thrown to the ground by wake turbulence taking off behind a heavy. Light aircraft can easely hit sinking air and are unable to climb out. So light aircraft are very much at the mercy of windshear and gusts.

Flying from the lightest to heavier aircraft is all about energy management from the aircraft engines to the airframe.

Fly close to the stall and hit a severe downdraft and you will end up stalling or in the trees.
1.3 times the stall plus half the gust factor is a good rule of thumb for the threshhold speed and higher on the approach. Speed is your saviour anything less and you are in the lap of the Gods.

Pace

BEagle
3rd Sep 2009, 10:46
I hope your experience with the dentist is as good as mine was on Tuesday, Lister! I hadn't seen a civilian dentist for over 40 years - and had never ever had any form of anaesthetic for a filling. The dentist was superb and I never felt a thing!

Pace, the issue is gust response and has nothing to do with engine response time. If Lister flies the way he's described, he will spot any wind shear immediately it occurs and will be able to correct instinctively - that's one of the many benefits of the point-and-power approach technique. Don't worry about the cause - just treat the effect!

25 gusting 50? No thanks! 20 gusting 30 - yes.

Legalapproach
3rd Sep 2009, 11:15
Lister,

I've checked, the Cub's free today so if you're back from the dentist it would be a good afternoon to go and try out some of the advice.

NORWICH AIRPORT EGSH 031100Z 0312/0321 25020G30KT 9999 SCT025 TEMPO 0312/0317 26025G40KT:E

Legal

Lister Noble
3rd Sep 2009, 12:55
Legal,do you fancy a spin this afternoon,the Cub is free;)?

The last time I flew the Cub on 23rd September the gusts were up to 30mph at Norwich,but straight down our N-S strip and I had no problem.
I had hoped to take the Cub to a local private airfield in the afternoon for a classic car rally,but the wind was straight across,so I took my old 1936 Riley Special instead
When I got there it was an MG car club meeting and there were some USAF personnel and pilots present with their cars.
I asked a C130 pilot what their cross wind limit was, he grinned and said,

"This is about it, depending on load"

He was riding a Harley,didn't ask crosswind for that:}

Later that day it died a bit, but still gusting well over 20mph and a P51 Mustang that lives there landed with two up,full fuel and luggage.
It really was a very skillful piece of flying.
:ok:
Due to the conditions the other Mustang that lives at the field put down at Tibbenham where they have a runway for every occassion:)
I arrived there next day to fly in a friends Condor as the Mustang took off,what a fantastic sound.

Lister:)

Pace
3rd Sep 2009, 13:05
Pace, the issue is gust response and has nothing to do with engine response time. If Lister flies the way he's described, he will spot any wind shear immediately it occurs and will be able to correct instinctively - that's one of the many benefits of the point-and-power approach technique. Don't worry about the cause - just treat the effect!

Beagle

Glad your experience with the dentist was good just had implant work done with a sinus lift advice to others dont go implant work unless your into serious pain and a serious knock on the bank balance :rolleyes:

Have flown a citation into Gatwick and Dundee with 60 kts gusts and windshear to give you the worst blow job you will ever have :E and Gatwick at night with the ASI jumping up and down 25 kts. But no intention of fighting you all to their own as they say :)

Pace

gasax
3rd Sep 2009, 13:39
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.

Pace
3rd Sep 2009, 13:56
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

Andy_RR
3rd Sep 2009, 14:37
...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

Lister Noble
3rd Sep 2009, 15:24
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:)

Pace
3rd Sep 2009, 15:43
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

BEagle
3rd Sep 2009, 17:10
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.

Andy_RR
3rd Sep 2009, 17:47
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

mary meagher
3rd Sep 2009, 20:52
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.

Lister Noble
4th Sep 2009, 08:02
Thanks for all the replies.
Maybe I've been doing it correctly anyway,following the POH,it worked for me.
Lister:)

hatzflyer
4th Sep 2009, 09:05
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?

Lister Noble
4th Sep 2009, 10:45
Hatz,I never knew that,but surely they have test flights before being certificated,and that would give all the required speeds etc?
Lister

Choxolate
4th Sep 2009, 11:02
Hatz,I never knew that,but surely they have test flights before being certificated,and that would give all the required speeds etc?
Lister
Yes they do - well at least my Europa does.

hatzflyer
4th Sep 2009, 11:20
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!:(

Lister Noble
4th Sep 2009, 11:42
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:)

S-Works
4th Sep 2009, 12:07
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.

hatzflyer
4th Sep 2009, 12:13
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.

gasax
4th Sep 2009, 12:31
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.

S-Works
4th Sep 2009, 12:38
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.

You are trying to play words. I clearly stated that they may not have a POH, but I will guarantee with my left testicle that all of the relevant speeds for those aircraft you are quoting have been tested and are known. Therefore whatever you want to refer to the 'book speed' as is available for those aircraft. You fly the approach based on those tested book speeds.

hatzflyer
4th Sep 2009, 12:59
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.

Choxolate
4th Sep 2009, 14:02
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 did not say it had a defintive POH I was agreeing that the various speeds are recorded for MY SPECIFIC aircraft at the time the aircraft was being test flown.

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)

hatzflyer
4th Sep 2009, 14:16
" yes they do- well at least my Europa does" ?????




Seems fairly unambiguous

Choxolate
4th Sep 2009, 14:27
Lister
Hatz,I never knew that,but surely they have test flights before being certificated,and that would give all the required speeds etc?Reply from me: Lister Yes they do - well at least my Europa does.

Hatz - "Seems fairly unambiguous "

Yes you are right - it is totally unambiguous that i was responding to the question about speeds being recorded and not about the presence of a POH.

hatzflyer
4th Sep 2009, 14:33
Obviously got the wrong end of the stick, thought you meant it HAS got a POH. So maybe it was ambiguous after all ! Sorry!

Choxolate
4th Sep 2009, 14:37
Obviously got the wrong end of the stick, thought you meant it HAS got a POH. So maybe it was ambiguous after all ! Sorry!
Apology accepted - not a problem.

One of the issues with the written word in forums (fora?) such as these - there appear to be more misunderstandings than understandings (if you see what I mean) - more of a problem with the medium - in a face to face conversation this type of misunderstoodification would not happen.

hatzflyer
4th Sep 2009, 14:41
I agree, the irony is that in a way you were agreeing with me in as far as not ALL aircraft have a POH! which was the point that got me steamed in the first place!:ok:

Choxolate
4th Sep 2009, 14:44
Life is full of these little ironies is it not? 'Tis what makes things interesting.

BEagle
4th Sep 2009, 14:51
Before you two get as far as tongues, my comment to Lister referred to his POH query concerning his Cub.

For aircraft which do not have a POH, obviously the parallel advice is to use the figures which the designer / LAA / AOPA / BMAA or whoever else regulates the aeronautical contraption o f your choice recommends.....:rolleyes:

gasax
4th Sep 2009, 14:57
But it gets better hatz - my permit aircraft has a POH available from several outfits whoi have or are building their versions which definitely does not apply to my aircraft!

However I have wondered why the TADS do not have some o fthe flight test data in them - they would at least then be a guide a to aircraft performance.

Choxolate
4th Sep 2009, 15:06
Before you two get as far as tonguesGot there about 20 minutes ago - we are getting married tomorrow


For aircraft which do not have a POH, obviously the parallel advice is to use the figures which the designer / LAA / AOPA / BMAA or whoever else regulates the aeronautical contraption o f your choice recommends.....Well I would use those as a GUIDE - my personal recommendation would be to find the actual stall speed in landing config. and then use this x1.3 for approach speed. This should be very close to, if not the same as, the "published" approach speed.

If it is very different I would refer to the kit provider, my LAA inspector, the LAA and other owners of same aircraft (in that order).

As for gusty landings use the same sources.

Other speeds (e.g. Vne) I stick to the kit providers published data.

BEagle
4th Sep 2009, 15:27
Got there about 20 minutes ago - we are getting married tomorrow

Yes, I understand that such things do go on in the Wild West....:ooh:

Your methodology sounds pretty good for a D-i-Y aircraft - but I still wouldn't recommend increasing your approach speed above whatever 1.3VS in the landing configuration at MAUW works out at. But then there's the issue of accurately determining VS in the first place if your homebuilt's pressure head has significant position error or other source of inaccuracy at low IAS.....

Pace
4th Sep 2009, 16:04
but I still wouldn't recommend increasing your approach speed above whatever 1.3VS in the landing configuration at MAUW works out at.

Beagle

I am struggling to understand your reasoning for the above comment? I am certainly not trying to get one up on you :O

Have you used the word approach meaning threshold speed? or do you mean at a busy airport you would fly down the approach at 1.3V in landing config regardless of other traffic wind turbulence or shear?

Maybe I am misunderstanding you?

Pace

Maoraigh1
4th Sep 2009, 16:17
Approach speed has nothing to do with touch-down speed. In calm air, I often fly 120+ knots on the approach to a 2000m runway, in a Jodel 1050, letting speed bleed off at roundout for a full stall touchdown. This allows me to fit in with commercial traffic.
Flying in to a 600 ft altitude hilltop airstrip, with wind reported over 20 knots, and gusting, at my 31 ft altitude departure airfield, I approached higher, and well above the recommended approach speed. I hit the downdraft and turbulence, then the windshear. Adding power, I landed comfortably on the upslope, using less than half the strip. Going round would not have been an option once into the downdraft.
See this FAA accident report. for severe gust conditions. http://www.ntsb.gov/ntsb/GenPDF.asp?id=DEN05LA112&rpt=fa
I have been told by instructors on Pa28/38 check outs that the approach should be stabilised by 200 ft. In gusty conditions, in a lightweight taildragger, I reckon I’m stabilised once I have 2 tiedowns secure, or the wings through the hangar door.

Pace
4th Sep 2009, 16:24
He "immediately initiated a go-around, applied full power, and set the attitude for level
flight.". He stated that "when the airplane entered the wind shear, the airspeed dropped rapidly
and the stall warning horn sounded". He said the airplane lost all lift and "slammed into the
runway".

To those who advocate 1.3 x stall in windy gusty and turbulence this is an extract from this reported accident so beware!


Pace

BEagle
4th Sep 2009, 19:47
Screw 'busy airports' forcing people to fly faster than is safe. If those in the tower can't cope with normal approach speeds for the type in question, that's their problem - they should have arranged appropriate spacing in the first place.

As for that 'report', what sort of idiot tries to conduct flight instruction with a wind of 09G37 with Cbs, virga and reported windshear at an airport with an elevation of nearly 4900 ft?

That sounds like an ideal roto streaming scenario. In usch circumstances, all bets are off for those of us flying puddlejumpers.

Maoraigh1
5th Sep 2009, 06:28
Air traffic have never suggested a fast approach. At most they say “ Report ready to turn base. We might squeeze you in if you keep it tight”. What’s wrong with not keeping people waiting?
The instructor in that report was not instructing a student. He was accompanying an experienced PPL from outside the area, who wanted to fly sight-seeing, but didn’t want to be checked out on an aircraft. CBs can develop quickly. He checked me out on several occasions, and I have great respect for him. I think his quoted hours do not include military hours.

Pace
5th Sep 2009, 07:43
Air traffic have never suggested a fast approach

Maoraigh1

Maybe not in uncontrolled airfields but it is totally normal in controlled airfields to fit in with other traffic. "Maintain 140 kts until 3 dme" or alternatively "reduce speed to X"

Speed control is about knowing your aircraft and having confidence in your abilities. Speed control is about energy and drag management and that should hold true from the lightest aircraft to the heaviest.

I note you are from Scotland so will be well brought up in handling strong winds :)


Pace

Andy_RR
5th Sep 2009, 10:14
As for that 'report', what sort of idiot tries to conduct flight instruction with a wind of 09G37 with Cbs, virga and reported windshear at an airport with an elevation of nearly 4900 ft?

On top of the gusting, it had a tailwind component of at least 10 deg, if not the full amount (runway 11, 21009G37KT, one observation at 31037KT)

Sounds like it was a challenging situation, but all the alarm bells should have been ringing loudly. I would have thought that 200', full power and the nose pointing downwards could have given you enough airspeed to clear the runway by at least a few feet, but then again, I wasn't there.

hatzflyer
7th Sep 2009, 08:26
"120knots + " in a jodel 1050 ? that can't be much below VNE !
The only time I saw 120knots in my 1050 was a full power dive!

Maoraigh1
7th Sep 2009, 20:32
It'll do 105kts cruise. Power on descent to runway, well below red line on tach, but in the yellow on the ASI. Did it again to avoid holding up someone last Saturday. Had a video camera on, but not showing instruments. Very gentle landing, no brake, and clear at middle of runway with no backtracking. (Original post was inaccurate in that runway is only just over 1800m)