Approach and landing speeds
Interestingly, it has come to my attention that a certain Oxonian flying school (not far from Mad Jamie's gaff) teaches its students that a Warrior's normal powered approach should be flown at 70 KIAS and that this speed may be increased 'slightly' (meaning what?) in conditions of (unspecified) turbulence - and that the 'threshold speed' should be increased by 5 kts with 3 or more PoB.....
DICKHEADS!!! READ THE POH!!!!!!
DICKHEADS!!! READ THE POH!!!!!!
Last edited by BEagle; 6th Jun 2003 at 05:51.
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Quite so BEagle, The reason I started this thread was because I am becoming increasingly concerned with the inability of the average PPL to land an aeroplane consistantly. I mean by that statement, with consistent technique. They can all land. Why is this?
I put it down to (and please don't anyone take offence as none is meant) the 250hr CAP 509 instructor culture.
I feel the comment made earlier by firefly bob makes my point.
I do check rides for for hirers fresh from these courses and generally the same observation as above applies. They try to fly a warrior or katana or whatever like a heavy jet because that is what they have been taught. Well, you cannot as the aerodynamics are different.
Before this becomes too gloomy a picture - I might add that I do see some very talented pilots with very low hrs.
How can you be expected to teach something that you do not understand yourself, especially if the goal is just to gain hrs? Surely the student suffers and the standards become increasingly bad.
I know there are a lot of us that do take the time to teach properly and I hope that this observation will be understood.
I put it down to (and please don't anyone take offence as none is meant) the 250hr CAP 509 instructor culture.
I feel the comment made earlier by firefly bob makes my point.
I do check rides for for hirers fresh from these courses and generally the same observation as above applies. They try to fly a warrior or katana or whatever like a heavy jet because that is what they have been taught. Well, you cannot as the aerodynamics are different.
Before this becomes too gloomy a picture - I might add that I do see some very talented pilots with very low hrs.
How can you be expected to teach something that you do not understand yourself, especially if the goal is just to gain hrs? Surely the student suffers and the standards become increasingly bad.
I know there are a lot of us that do take the time to teach properly and I hope that this observation will be understood.
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Here. Here. Quite so PilotBear.
Re: Seamanship - Im gonna take the Commercial paper - I did the PPL paper merely for rating issue as the CAA have to arrange specific exam dates - so Im starting to study again now so that I can get the last bit sorted
Re: Seamanship - Im gonna take the Commercial paper - I did the PPL paper merely for rating issue as the CAA have to arrange specific exam dates - so Im starting to study again now so that I can get the last bit sorted
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Pilotbear, formationflyer:
I'm also planning to take the Seamanship exam at commercial level sometime soon. I wonder if either (or both) of you would be interested in corresponding to exchange study notes and ideas, clarify what's required, etc. If so please feel free to PM or email me via Pprune. Pilotbear I gather you already have the CPL sea qualification - any exam tips most welcome.
One way or the other... good luck, chaps....
I'm also planning to take the Seamanship exam at commercial level sometime soon. I wonder if either (or both) of you would be interested in corresponding to exchange study notes and ideas, clarify what's required, etc. If so please feel free to PM or email me via Pprune. Pilotbear I gather you already have the CPL sea qualification - any exam tips most welcome.
One way or the other... good luck, chaps....
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Yes I do have the Commercial Seaplane licence. I would be happy to help. Send me your email address to the pprune email address.
Mostly concentrate on Bouys (know them absolutely), Lights on the the water and rights of way on the water.
Mostly concentrate on Bouys (know them absolutely), Lights on the the water and rights of way on the water.
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PA28 approach speeds
Ahhhhh, you've really poked my nest now. I have recently been trying to make sense of the POHs, including the UK Supplements, for the Warrior and Archer. The former advocates an approach speed of 63kts irrespective of weight, the latter a variety of speeds ranging from 75kts at max weight down to 63kts at 1800lbs.
I can't see the logic in this. I can see that the extra 10% weight of an Archer should require a higher Vref than the Warrior, but why so high? If you come down the approach at 75kts in a fully-laden Archer you will find it difficult to get rid of the 11kts or so necessary to bring you down to Vat.
And why no reduction in speed for the Warrior when operating at less than max weight?
I can't see the logic in this. I can see that the extra 10% weight of an Archer should require a higher Vref than the Warrior, but why so high? If you come down the approach at 75kts in a fully-laden Archer you will find it difficult to get rid of the 11kts or so necessary to bring you down to Vat.
And why no reduction in speed for the Warrior when operating at less than max weight?
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North SOuth - I recently notice the same oddity on the POH for an Arrow II. Whilst 1.3 Vs1 is approx 60kts, the poh approach speeds varies in a linear fashion from, if I recall correctly, 78kts to 66kts. Actually, that may have been for the PA32, I dont have the figures to hand, but I do know that the lowest approach speed recommended in the POH (which incidentally was for zero fuel weight - ?!) is significantly more than 1.3 VS1. Is it normal practise to land larger light aircraft on the edge of the stall, like a small cesssna, or is it recommended practise to touch down with more control authority at a slightly higher speed, though, inevitably, a smaller percentage increase than say touching down at 65kts in a Warrior?
Do a Hover - it avoids G
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I am not taking sides here because I don’t know enough about the specific types being talked about.
However, while 1.3 Vs is certainly the certification basis so far as lift goes, do not forget the issue of controllability.
Quite a lot of aircraft have minimum speeds higher than 1.3Vs to improve controllability. A non controversial one (in this forum) being the Vulcan, more lift than you could ever want but lateral control in turbulence set a min speed of 125 even at the lightest weights. So it did with the Viscount. And closer to home (here) so it did with Dove G-ASMG if there were serious turbs about.
However, while 1.3 Vs is certainly the certification basis so far as lift goes, do not forget the issue of controllability.
Quite a lot of aircraft have minimum speeds higher than 1.3Vs to improve controllability. A non controversial one (in this forum) being the Vulcan, more lift than you could ever want but lateral control in turbulence set a min speed of 125 even at the lightest weights. So it did with the Viscount. And closer to home (here) so it did with Dove G-ASMG if there were serious turbs about.
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I find that on the Arrow or Archer with the straight wing that 65 kt threshold with power works really well with negligable flaring required. Power off on TD.
However, that cursed warrior with the tapered wing will not touchdown at more than 60kts so you just have to be patient with it and not try to force it to come down. It is not a good aeroplane if you are ground shy. However, it seems to be a better aircraft for power off over the threshold landings provided you cross at 65kt (full flap).
However, that cursed warrior with the tapered wing will not touchdown at more than 60kts so you just have to be patient with it and not try to force it to come down. It is not a good aeroplane if you are ground shy. However, it seems to be a better aircraft for power off over the threshold landings provided you cross at 65kt (full flap).
Approach Speeds & 'Controllability'
In a perfect world - we would all use 1.3Vsf, and that would be it.
Of course, this number changes with several factors,so it would differ from flight to flight - hence common practice is to use Vsf @ MAUW as the reference. This gives a number which is almost always higher than 1.3Vsf 'on the day'. So, we are going too fast, before we begin to add 5KIAS for Mum and the kids, and another 5KIAS for grannie, and 5 more for the insurers etc.
In the real world, turbulence and wind shear lurk in waiting near the ground. Because of them, there can be stall warning incursions as we slow to Vsf, and this frightens not just the passengers, but also the student. This particularly so if said student has been trained to beleive that the onset of stall warning is highly dangerous and to be avoided at all cost.
One of the main reasons I hear for higher approach speeds is that your ailerons are more effective, and a dropped wing can be quickly picked up, and the aircraft can be cross controlled for a cross wind landing without going too near stall. There is a certain fearful logic to this in windy conditions, and where shear is likely, as behind trees, buildings.
Would this work for a pilot landing on a short strip in Alaska,PNG,outback Aus - or anywhere for that matter? Hell no - you'll be off the end and into the scrub! Do they exceed 1.3 Vsf - not b....y likely! So how do they manage, and is there a lesson there for Mr average PPL flying into a country airport or farm strip?
So- what about RUDDER? Go back to Lesson 1 Effect and Operation of Controls. Why do we show students the secondary effects of controls? For the good of their health? Is their any application of this knowledge in later flying? No,Yes? Of course there is - and it's never so useful as on approach in turbulence and shear. Don't think that shear is just some phenomhena associated with obstacles and gales either. It's everywhere. And once mastered, using rudder intelligently will smooth out your S&L - particularly in rough air.
What about other controls? POWER should be used sparingly, but if you don't use it, then icing is much more likely, and a baulked approach is delayed by having to 'ease' the throttle through the first couple hundred RPM, or the engine can falter alarmingly. Better to have a little power on, for this, and for better RUDDER controllability.
As you continue down final, shear will cause you to suffer decreased IAS/or increased ROD, or both, unless you ADD POWER. Often, you can anticipate these effects, and add power on cutting the top - of - obstacle line. In winds over 20 kts on open ground, probably at 200 ft you could start. By doing this, 1.3 Vsf is maintained, as is the angle of approach, without having to lose it first. Prevention is better than cure!
Now, we're at 200 ft on final, and strike turbulence/shear, the aircraft drops a wing and sinks. First reaction of student is to heave ho on the elevators and muscle in big amounts of aileron. We're now off on a low speed 'snaking' approach, of the falling leaf type mentioned by earlier posts. Isn't it far easier to use those feet, applying rudder to pick up the low wing, (via the secondary effect), and adding some power? You avoid the snake, and the ROD increase,and the IAS decrease, all in a very short time.
By avoiding this horrendous 'snake' effect, the pilot can keep focussed on the aiming point, and prepare for the crosswind correction inputs as necessary.
Therefore, I offer no support for increased approach speeds, because the means, (power + rudder), are at hand to hold Vsf without struggling for control.
Instructors - it's in your court to fix this high speed approach problem.
cheers,
In a perfect world - we would all use 1.3Vsf, and that would be it.
Of course, this number changes with several factors,so it would differ from flight to flight - hence common practice is to use Vsf @ MAUW as the reference. This gives a number which is almost always higher than 1.3Vsf 'on the day'. So, we are going too fast, before we begin to add 5KIAS for Mum and the kids, and another 5KIAS for grannie, and 5 more for the insurers etc.
In the real world, turbulence and wind shear lurk in waiting near the ground. Because of them, there can be stall warning incursions as we slow to Vsf, and this frightens not just the passengers, but also the student. This particularly so if said student has been trained to beleive that the onset of stall warning is highly dangerous and to be avoided at all cost.
One of the main reasons I hear for higher approach speeds is that your ailerons are more effective, and a dropped wing can be quickly picked up, and the aircraft can be cross controlled for a cross wind landing without going too near stall. There is a certain fearful logic to this in windy conditions, and where shear is likely, as behind trees, buildings.
Would this work for a pilot landing on a short strip in Alaska,PNG,outback Aus - or anywhere for that matter? Hell no - you'll be off the end and into the scrub! Do they exceed 1.3 Vsf - not b....y likely! So how do they manage, and is there a lesson there for Mr average PPL flying into a country airport or farm strip?
So- what about RUDDER? Go back to Lesson 1 Effect and Operation of Controls. Why do we show students the secondary effects of controls? For the good of their health? Is their any application of this knowledge in later flying? No,Yes? Of course there is - and it's never so useful as on approach in turbulence and shear. Don't think that shear is just some phenomhena associated with obstacles and gales either. It's everywhere. And once mastered, using rudder intelligently will smooth out your S&L - particularly in rough air.
What about other controls? POWER should be used sparingly, but if you don't use it, then icing is much more likely, and a baulked approach is delayed by having to 'ease' the throttle through the first couple hundred RPM, or the engine can falter alarmingly. Better to have a little power on, for this, and for better RUDDER controllability.
As you continue down final, shear will cause you to suffer decreased IAS/or increased ROD, or both, unless you ADD POWER. Often, you can anticipate these effects, and add power on cutting the top - of - obstacle line. In winds over 20 kts on open ground, probably at 200 ft you could start. By doing this, 1.3 Vsf is maintained, as is the angle of approach, without having to lose it first. Prevention is better than cure!
Now, we're at 200 ft on final, and strike turbulence/shear, the aircraft drops a wing and sinks. First reaction of student is to heave ho on the elevators and muscle in big amounts of aileron. We're now off on a low speed 'snaking' approach, of the falling leaf type mentioned by earlier posts. Isn't it far easier to use those feet, applying rudder to pick up the low wing, (via the secondary effect), and adding some power? You avoid the snake, and the ROD increase,and the IAS decrease, all in a very short time.
By avoiding this horrendous 'snake' effect, the pilot can keep focussed on the aiming point, and prepare for the crosswind correction inputs as necessary.
Therefore, I offer no support for increased approach speeds, because the means, (power + rudder), are at hand to hold Vsf without struggling for control.
Instructors - it's in your court to fix this high speed approach problem.
cheers,
Disagree with using rudder as an aileron replacement. Use the controls in a co-ordinated manner. Otherwise pretty much what was said, esp. using power. I fly in some high winds,very rough, high windshear conditions and it's quite common for me to need to vary between full power & idle and this is into very short strips (380m the shortest) with obstacles.
Quite so. Large, uncoordinated rudder deflections at low IAS positively invite disaster. Just use the rudder to keep the ball in the middle and the control column to maintain the required attitude.
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The problem with using aileron in the appraoach is as you know if a wing drops it will usually return by itself, and usually just as the student is applying the aileron correction ending up with a wing drop in the other direction. Gentle use of rudder assisted with a little aileron helps the nose remain pointed at the runway and eliminates the falling leaf.
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Lost me too Im afraid. I cant say that coordinated use of aileron and rudder to balance left me in a 'falling leaf' scenario - indeed - if you pick the wing up fast enough with aileron then all you have done is roll - no yaw had time to affect the aircraft...
One exercise I do with my students in med level turns - pior to going through the turn is to 'roll around a point'....its an exercise in foot control - all planes have adverse yaw - even nice PA28 & C152 do. So I roll the wings back and forth which shows the student how much adverse yaw is apparent - and the balance ball is diving out all over the place. I then show that by coordinated use of the controls I can remove all visual artifacts of yaw and the aircraft rolls around a point - and the ball stays in the middle - it is then impressed on them that the amount of rudder needed is directly proportional to the amount of deflection of the aileron and that they must remember how much rudder they had to use - as the same amount will be needed when rolling into turns...i.e. use your feet....
Now...back to the approach wing drop...anyone who advocates use of rudder to 'pick up wings' is asking for trouble. stall + yaw = spin. Yep. But how many of you impress upon the student that if the aircraft (or part of it) stalls with yaw already presented that a flick/spin will result - ask your students - I have had answers from 2-5 seconds after a stall with yaw before the spin starts....they are most suprised when I tell them that the spin can start sub-second and that some a/c can flick very violently....
Re: student who applies to much aileron....well if they are looking out the front that wont happen - either that or they need to be lighter, less cumbersome and quicker on the controls...which is something they learn..I think its wrong to teach bad habits to correct minor, newbie 'habits'.
Regards,
FF
One exercise I do with my students in med level turns - pior to going through the turn is to 'roll around a point'....its an exercise in foot control - all planes have adverse yaw - even nice PA28 & C152 do. So I roll the wings back and forth which shows the student how much adverse yaw is apparent - and the balance ball is diving out all over the place. I then show that by coordinated use of the controls I can remove all visual artifacts of yaw and the aircraft rolls around a point - and the ball stays in the middle - it is then impressed on them that the amount of rudder needed is directly proportional to the amount of deflection of the aileron and that they must remember how much rudder they had to use - as the same amount will be needed when rolling into turns...i.e. use your feet....
Now...back to the approach wing drop...anyone who advocates use of rudder to 'pick up wings' is asking for trouble. stall + yaw = spin. Yep. But how many of you impress upon the student that if the aircraft (or part of it) stalls with yaw already presented that a flick/spin will result - ask your students - I have had answers from 2-5 seconds after a stall with yaw before the spin starts....they are most suprised when I tell them that the spin can start sub-second and that some a/c can flick very violently....
Re: student who applies to much aileron....well if they are looking out the front that wont happen - either that or they need to be lighter, less cumbersome and quicker on the controls...which is something they learn..I think its wrong to teach bad habits to correct minor, newbie 'habits'.
Regards,
FF
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ive been flying for nearly 15 years now in many different area's from light singles up to light weight jets.an interesting comment that ive heard many times from many different pilots is that "0h thats a real numbers a\c,fly it by the numbers and it does just what you want it to".(regarding a specific type)
well guess what guys,thats what the POH is for in any a/c type.
it doesnt make any difference if your flying a c-152 or a learjet,VFR or IFR if you fly it by the numbers it works
ps this is not having a go at anyone on here just a general observation
cheers
well guess what guys,thats what the POH is for in any a/c type.
it doesnt make any difference if your flying a c-152 or a learjet,VFR or IFR if you fly it by the numbers it works
ps this is not having a go at anyone on here just a general observation
cheers
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I checked my POH this weekend, and its states that the approach speed for this PA28 Arrow II is between 80kts at 1800lbs and 90kts at 2600lbs on a linear scale. However, Vs is about 56kts at max weight, 1.3vs is therefore 73kts, but flying the numbers means I have to lose up to 34kts before touchdown. Well, I got a friend to concentrate on my ASI on sat evening when all was calm. He noted that I approached at 80kts, then over the threshold at 75kts, rounding out, then a hold off and touchdown at just below 60. Distance from the numbers to walking pace was about 400m with slight down slope. It doesnt take long in an arrow with full flap gear down, level flight, idle power to lose 15kts.
Pilotbear, I cant say I aim for a particular threshold speed. I just try and reduce whatever my approach speed is, to a touchdown as slow as poss. Sometimes I'll approach faster and when I know I am going to make it, reduce power, and decelerate in anticipation of the flare.
Pilotbear, I cant say I aim for a particular threshold speed. I just try and reduce whatever my approach speed is, to a touchdown as slow as poss. Sometimes I'll approach faster and when I know I am going to make it, reduce power, and decelerate in anticipation of the flare.
