Risk of spinning from a sideslip?
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Risk of spinning from a sideslip?
What is the risk of converting a badly judged sideslip into a spin? I have been practising sideslipping under instruction (so far from a safe height) but no-one seems to be able to answer this question to my satisfaction. In a sideslip, you have an airplane out of balanced flight, full rudder, a raised nose attitude and unreliable airspeed indication. Prime risk factors for a spin I would have thought and at circuit height, which is where most folk use a sideslip for real, unrecoverable. Nonetheless all the pundits who fly "real" airplanes advise using a slideslip from time to time, and it always comes out in advice on forced landings. Advice from anyone with experience would be welcome. Thanks.
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Sideslipping and risk of spinning
Hi Oscar
Having done loads of spinning this year on a gliding instructor's course, my twopennorth is as follows. A classic spin entry is an over-ruddered turn at low speed, whereas in the sideslip situation you describe, you have exactl the opposite - in other words, loads of out-of-turn rudder, so the configuration is inherently spin-resistant. The biggest problem is recovery from the sideslip just before the flare, assuming that you are sideslipping as a last resort to burn off energy and avoid an overshoot. As you recover, your ASI reading is, as you say, unreliable, and it is pretty easy to recover at the wrong attitude at a fairly critical moment and potentially stall in. This is one reason cited for sideslipping no longer being on the BGA pre-solo syllabus (whereas it was when I was learning 15 years ago). The other reason invoked by many for sideslipping coming off the syllabus is that modern gliders are so streamlined that offering up the fuselage side to the airflow does little to reduce drag, and therefore renders the sideslip pretty pointless. Doesn't mean to say that I don't still sideslip from time to time when an embarrassing overshoot a hundred yards past the launch point is on the cards !
Having done loads of spinning this year on a gliding instructor's course, my twopennorth is as follows. A classic spin entry is an over-ruddered turn at low speed, whereas in the sideslip situation you describe, you have exactl the opposite - in other words, loads of out-of-turn rudder, so the configuration is inherently spin-resistant. The biggest problem is recovery from the sideslip just before the flare, assuming that you are sideslipping as a last resort to burn off energy and avoid an overshoot. As you recover, your ASI reading is, as you say, unreliable, and it is pretty easy to recover at the wrong attitude at a fairly critical moment and potentially stall in. This is one reason cited for sideslipping no longer being on the BGA pre-solo syllabus (whereas it was when I was learning 15 years ago). The other reason invoked by many for sideslipping coming off the syllabus is that modern gliders are so streamlined that offering up the fuselage side to the airflow does little to reduce drag, and therefore renders the sideslip pretty pointless. Doesn't mean to say that I don't still sideslip from time to time when an embarrassing overshoot a hundred yards past the launch point is on the cards !
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As is often said, perhaps a good idea to discuss your concerns with the instructor, however, In my opinion the risk is minimal, however, ther usual caveat applies - don't go and risk your skin based on what I write!
Firstly your nose angle shouldn't be any higher than it would be for that phase of flight without the sideslip. You may however require a more rearward stick position to achieve that nose angle (elevator blanking)
As per my understanding of the aerodynamics, a spin doesn't just require out of balance flight, it requires one of the wings to be travelling faster, i.e. an increasing yaw angle, not a static, large yaw angle - what you need is one wing to stall before the other, hence the speed difference (and this is limited to straight wings, not swept).
Theory aside, in practice it's harder than people would have you believe to get most aeroplanes to spin (my experience is in a/c certified for spinning, so limited to those with reasonable spin characteristics). Most will give you an attention grabbing wing drop at the stall, but it requires persistent effort (or mishandling) to create a spin - if you relax the back pressure after the wing drop you'll just fly out of it. Further, most types I've flown don't want to spin once stalled - you have to be pushing yaw in at the right time (just around the stall) to get the spin.
I also conducted an experiment in a decathlon to test exactly this question - I went up to 5000ft, crossed it all up into the biggest sideslip I could create, and stalled it. It dropped clean and straight ahead. Again the caveat - I've been trained, signed off, and have spun a lot - don't tempt fate if you're not familiar spinning.
All that said, even a straight stall near the ground is bad news. Realistically though, your approach speed normally gives a pretty decent margin over the stall. Cues like stick position and pitch angle should complete the picture. If the stick keeps coming back, that's bad - if it stays forward of a certain point, the a/c cannot stall.
Frankly it's a wonderful tool to have in your box of tricks, but be comfortable with it, before you need it
Edit to add:
Pegpilot: The a/c will spin either way quite happily - in fact the usual reaction to stall in a turn is that the a/c flicks away from the turn (I don't know why, sorry!); it's just that the over-ruddered final turn is the classic way to set up a spin in a glider - especially if you're stretching the glide a bit, are low, slow, and those long wings seem awful close to the ground.. (Yes, also a glider pilot..)
When I did sideslipping in a glider it was hammered into me to memorise the pitch angle before sideslipping, and maintain the nose at, or slightly lower than that - speed would then be bang on when you straightened up. Complicated by use of the noise lever in a powered a/c, but the basic principle still applies. (Power+Pitch=Performance).
Firstly your nose angle shouldn't be any higher than it would be for that phase of flight without the sideslip. You may however require a more rearward stick position to achieve that nose angle (elevator blanking)
As per my understanding of the aerodynamics, a spin doesn't just require out of balance flight, it requires one of the wings to be travelling faster, i.e. an increasing yaw angle, not a static, large yaw angle - what you need is one wing to stall before the other, hence the speed difference (and this is limited to straight wings, not swept).
Theory aside, in practice it's harder than people would have you believe to get most aeroplanes to spin (my experience is in a/c certified for spinning, so limited to those with reasonable spin characteristics). Most will give you an attention grabbing wing drop at the stall, but it requires persistent effort (or mishandling) to create a spin - if you relax the back pressure after the wing drop you'll just fly out of it. Further, most types I've flown don't want to spin once stalled - you have to be pushing yaw in at the right time (just around the stall) to get the spin.
I also conducted an experiment in a decathlon to test exactly this question - I went up to 5000ft, crossed it all up into the biggest sideslip I could create, and stalled it. It dropped clean and straight ahead. Again the caveat - I've been trained, signed off, and have spun a lot - don't tempt fate if you're not familiar spinning.
All that said, even a straight stall near the ground is bad news. Realistically though, your approach speed normally gives a pretty decent margin over the stall. Cues like stick position and pitch angle should complete the picture. If the stick keeps coming back, that's bad - if it stays forward of a certain point, the a/c cannot stall.
Frankly it's a wonderful tool to have in your box of tricks, but be comfortable with it, before you need it
Edit to add:
Pegpilot: The a/c will spin either way quite happily - in fact the usual reaction to stall in a turn is that the a/c flicks away from the turn (I don't know why, sorry!); it's just that the over-ruddered final turn is the classic way to set up a spin in a glider - especially if you're stretching the glide a bit, are low, slow, and those long wings seem awful close to the ground.. (Yes, also a glider pilot..)
When I did sideslipping in a glider it was hammered into me to memorise the pitch angle before sideslipping, and maintain the nose at, or slightly lower than that - speed would then be bang on when you straightened up. Complicated by use of the noise lever in a powered a/c, but the basic principle still applies. (Power+Pitch=Performance).
Last edited by Mark1234; 20th Nov 2009 at 10:10.
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Get the Approach right
I do not like side slipping. I know plenty of pilots do it, but I would rather get the circuit/approach/final correct which in turn leads to a good landing (generally). I have witnessed some horror stories where pilots side slipped from great hight on final, in fact one just two weeks ago where I highly experienced aerobatic pliot, my friend who was joining me for lunch, saved a full ground loop by the skin of his teeth - quote 'should have gone around from that final'
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I know where Mark1234 is from and I fully agree with him. Just one more point:
I would certainly hope that you do NOT have a raised nose attitude, at least not raised above the normal angle for your speed, power setting and phase of flight.
The typical reason for sideslipping is to wash off excess energy (altitude and/or speed) in the final approach phase, where flaps and/or airbrakes are not available or not sufficient. So you need to find another way to increase drag, and that's by using the full fuselage.
Drag is exponentially proportional to speed, so the most effective sideslip is one that is done at relatively high speed. So a sideslip just above the stall isn't nearly as effective as a sideslip performed at 1.3xVs or even higher. That should keep you well away from the stall and thus from the spin.
This is also the reason that you will want to LOWER the nose a bit in a sideslip. You've just greatly increased the drag and if you maintain the same attitude, you'll maintain the same glide slope, but with reducing speed. Not what you set out to achieve, normally.
Caveat here of course: the side loads on the fin & rudder in a sideslip are huge. You do not want to be much above your typical approach speed or risk breaking the plane. But I have to admit I do not know how to find/calculate the exact limit, or what normal certification limits are. I would not assume automatically that if you stay below Va, you can't break off the rudder. The aerobatic airplane I fly has a specific limit for flick rolls, (92 knots) and for sideslipping I would use the same limit. (Va is 127 knots in that aircraft, for comparison.)
In a sideslip, you have an airplane out of balanced flight, full rudder, a raised nose attitude and unreliable airspeed indication.
The typical reason for sideslipping is to wash off excess energy (altitude and/or speed) in the final approach phase, where flaps and/or airbrakes are not available or not sufficient. So you need to find another way to increase drag, and that's by using the full fuselage.
Drag is exponentially proportional to speed, so the most effective sideslip is one that is done at relatively high speed. So a sideslip just above the stall isn't nearly as effective as a sideslip performed at 1.3xVs or even higher. That should keep you well away from the stall and thus from the spin.
This is also the reason that you will want to LOWER the nose a bit in a sideslip. You've just greatly increased the drag and if you maintain the same attitude, you'll maintain the same glide slope, but with reducing speed. Not what you set out to achieve, normally.
Caveat here of course: the side loads on the fin & rudder in a sideslip are huge. You do not want to be much above your typical approach speed or risk breaking the plane. But I have to admit I do not know how to find/calculate the exact limit, or what normal certification limits are. I would not assume automatically that if you stay below Va, you can't break off the rudder. The aerobatic airplane I fly has a specific limit for flick rolls, (92 knots) and for sideslipping I would use the same limit. (Va is 127 knots in that aircraft, for comparison.)
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Maxred - to an extent a fair point, get it right and never be shy to go around. However, getting the approach right is rather separate from sideslipping. The sideslip is a useful tool, and in some cases a necessary part of a correct approach (e.g. pitts!), not just something to rescue a bad approach. There should be no reason for sideslipping to lead to a groundloop.
It's a bit like flying upside down, do it enough and you might even like it
It's a bit like flying upside down, do it enough and you might even like it
I'm not an instructor so don't take my views without a pinch of salt (and confirmation from a reliable source), but I've always understood a sideslip is safe, provided you don't let the speed fall. Keep well above normal stall speed, which generally means keeping the nose down, not up.
And sideslip means rudder opposed to ailerons: you're pressing the rudder on the high wing side, against the bank.
Top rudder: good
Bottom rudder: bad
And sideslip means rudder opposed to ailerons: you're pressing the rudder on the high wing side, against the bank.
Top rudder: good
Bottom rudder: bad
Last edited by FREDAcheck; 20th Nov 2009 at 13:00.
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Neither am I an instructor.. but I've probably spun more than most instructors 
In fairness I should disclaim; I'm just a regular PPL, though I've had the fortune to fly with some very good pilots as instructors, done a lot of 'beyond ppl' training, and come through a more stick and rudder oriented route than most. I'm also (in case you didn't guess) in fairly regular aerobatic practice. [end disclaimer].
Fancy meeting you here BackPacker
My understanding is that Va is the most limiting speed for any *single* full control deflection; JAR23 would seem to confirm this (pasted at the end) That's not a license to abuse the airframe, but Flicks/Snaps are a 'special case' as you're being pretty brutal with the rudder AND the elevator together. That said a sideslip is also a multi control deflection, though hopefully not as aggressive! I'd not be too paranoid about overstressing the a/c sideslipping.
In fairness I should disclaim; I'm just a regular PPL, though I've had the fortune to fly with some very good pilots as instructors, done a lot of 'beyond ppl' training, and come through a more stick and rudder oriented route than most. I'm also (in case you didn't guess) in fairly regular aerobatic practice. [end disclaimer].Fancy meeting you here BackPacker
My understanding is that Va is the most limiting speed for any *single* full control deflection; JAR23 would seem to confirm this (pasted at the end) That's not a license to abuse the airframe, but Flicks/Snaps are a 'special case' as you're being pretty brutal with the rudder AND the elevator together. That said a sideslip is also a multi control deflection, though hopefully not as aggressive! I'd not be too paranoid about overstressing the a/c sideslipping.
JAR 23.441 Manoeuvring loads
(a) At speeds up to VA the vertical surfaces must be designed to withstand the following conditions. In computing the loads, the yawing velocity may be assumed to be zero:
(1) With the aeroplane in unaccelerated flight at zero yaw, it is assumed that the rudder control is suddenly displaced to the maximum deflection, as limited by the control stops or by limit pilot forces.
(2) With the rudder deflected as specified in sub-paragraph (1) of this paragraph, it is assumed that the aeroplane yaws to the overswing side-slip angle. In lieu of a rational analysis, an overswing angle equal to 1·5 times the static sideslip angle of sub-paragraph (3) of this paragraph may be assumed.
(3) A yaw angle of 15° with the rudder control maintained in the neutral position (except as limited by pilot strength).
(b) In addition for commuter category aeroplanes, the following manoeuvre must be considered at speeds from VA up to VD/MD. In computing the tail loads, the yawing velocity may be assumed to be zero; with the aeroplane yawed to the static sideslip angle corresponding to the maximum rudder deflection, as limited by the control surface stops or the maximum available booster effort, or the maximum pilot rudder force as specified by JAR 23.397 (b) at VA and 2/3 of the maximum pilot force specified by JAR 23.397(b) from VC/MC to VD/MD, with linear variations between VA and VC/MC, it is assumed that the rudder control is suddenly returned to neutral.
(c) The yaw angles specified in sub-paragraph (a) (3) of this paragraph may be reduced if the yaw angle chosen for a particular speed cannot be exceeded in -
(1) Steady slip conditions;
(2) Uncoordinated rolls from steep banks; or
(3) Sudden failure of the critical engine with delayed corrective action.
(a) At speeds up to VA the vertical surfaces must be designed to withstand the following conditions. In computing the loads, the yawing velocity may be assumed to be zero:
(1) With the aeroplane in unaccelerated flight at zero yaw, it is assumed that the rudder control is suddenly displaced to the maximum deflection, as limited by the control stops or by limit pilot forces.
(2) With the rudder deflected as specified in sub-paragraph (1) of this paragraph, it is assumed that the aeroplane yaws to the overswing side-slip angle. In lieu of a rational analysis, an overswing angle equal to 1·5 times the static sideslip angle of sub-paragraph (3) of this paragraph may be assumed.
(3) A yaw angle of 15° with the rudder control maintained in the neutral position (except as limited by pilot strength).
(b) In addition for commuter category aeroplanes, the following manoeuvre must be considered at speeds from VA up to VD/MD. In computing the tail loads, the yawing velocity may be assumed to be zero; with the aeroplane yawed to the static sideslip angle corresponding to the maximum rudder deflection, as limited by the control surface stops or the maximum available booster effort, or the maximum pilot rudder force as specified by JAR 23.397 (b) at VA and 2/3 of the maximum pilot force specified by JAR 23.397(b) from VC/MC to VD/MD, with linear variations between VA and VC/MC, it is assumed that the rudder control is suddenly returned to neutral.
(c) The yaw angles specified in sub-paragraph (a) (3) of this paragraph may be reduced if the yaw angle chosen for a particular speed cannot be exceeded in -
(1) Steady slip conditions;
(2) Uncoordinated rolls from steep banks; or
(3) Sudden failure of the critical engine with delayed corrective action.
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Sideslipping is a very useful proceedure to have in your back pocket for any emergency landing. It allows you to carry a bit of speed/height and to lose it when you are sure you will make the field.
In many taildraggers it allows a good look forward. Practice it up high first as it does feel strange at first. Also make sure you can side slip both ways (left and right) as its best to have the nose into wind when you have a crosswind.
The nose will need to be lowered to keep the speed up.
Once you have mastered it you will wonder why you worried about it.
ZA
In many taildraggers it allows a good look forward. Practice it up high first as it does feel strange at first. Also make sure you can side slip both ways (left and right) as its best to have the nose into wind when you have a crosswind.
The nose will need to be lowered to keep the speed up.
Once you have mastered it you will wonder why you worried about it.
ZA
ZA has it right in getting rid of excess energy that you have rightfully kept in your pocket.
In an emergency landing your aim point is well down the field. Once the field is made, it's nice to have a longer landing run or pick out the best touchdown spot.
In a normal landing, I like to have something extra in case the engine coughs or stops.
In earlier gliders, the spoilers were often not that powerful; so sideslips or higher speed to increase drag are often called for.
In the newer gliders, the handbook often cautions against full spoilers on touchdown; so, you have to reduce to half or so just before the flare -- or be just a few inches up as when you're picking the smoothest part of a field.
You need to come out of the sideslip a comfortable distance above the flare. As you become more attuned to the a/c, this altitude can get lower.
In an emergency landing your aim point is well down the field. Once the field is made, it's nice to have a longer landing run or pick out the best touchdown spot.
In a normal landing, I like to have something extra in case the engine coughs or stops.
In earlier gliders, the spoilers were often not that powerful; so sideslips or higher speed to increase drag are often called for.
In the newer gliders, the handbook often cautions against full spoilers on touchdown; so, you have to reduce to half or so just before the flare -- or be just a few inches up as when you're picking the smoothest part of a field.
You need to come out of the sideslip a comfortable distance above the flare. As you become more attuned to the a/c, this altitude can get lower.
Most of the above appears to be experiences and general opinion.
So here's my penn'orth !
a) Flying into a strip(s) for well over 30 years in 65 to 100 h.p light a/c, side slip is a wonderful tool to help arrive at a safer speed & height to clear the obstacles, trees, fences etc. on short finals should the engine play up.
And THEN get rid of the all excess before straightening up with a hand ready on the throttle just in case you over cook it & need cushioning burst of full power.
b) I too was never sure about the safe low speed end to use. Right or wrong I do full rudder side slips at ias no slower than recommended finals speed. i.e ias stall plus minimum 20 %.
Seems to work though you may know better.
Mike Hallam.
So here's my penn'orth !
a) Flying into a strip(s) for well over 30 years in 65 to 100 h.p light a/c, side slip is a wonderful tool to help arrive at a safer speed & height to clear the obstacles, trees, fences etc. on short finals should the engine play up.
And THEN get rid of the all excess before straightening up with a hand ready on the throttle just in case you over cook it & need cushioning burst of full power.
b) I too was never sure about the safe low speed end to use. Right or wrong I do full rudder side slips at ias no slower than recommended finals speed. i.e ias stall plus minimum 20 %.
Seems to work though you may know better.
Mike Hallam.
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The pitch attitude is flatter in a side slip. If you keep the same attitude in the slip the speed will be higher when you straighten out again. If you have done this to the groubd you will then have loads of speed, in ground effect, and float for miles.
Take a CD and draw an aeroplane planform on it. Then put it at a slight angle and turn it about the hole in the middle. There you go, a flatter attitude. If you turn it 90 degrees it will be level.
Nothing more satisfying than the transition from slip to flare and three pointer.
Take a CD and draw an aeroplane planform on it. Then put it at a slight angle and turn it about the hole in the middle. There you go, a flatter attitude. If you turn it 90 degrees it will be level.
Nothing more satisfying than the transition from slip to flare and three pointer.
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Surely you sometimes need a bit of back pressure while you're actually in the slip?
Your best bet to determine how much backpressure is required, is to look out the window to the spot where you want to go. See if the aspect of the surrounding terrain changes to judge your approach angle. And use clues like wind noise, stiffening of controls, buffeting and so forth to determine if the speed is ok. You can't trust the ASI as an absolute indication of airspeed in a sideslip, but generally if the ASI shows an increase during the slip, you are indeed gaining speed and vice versa.
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[edited as I'm starting to repeat my previous posts]
Miserlou, I'm afraid I disagree - you are right about the geometry, however, the angles of slip we are considering are fairly small (<30deg), minimising the geometric effect. Generally (and I'm sure there will be exceptions), the predominant effect is increased drag as the relative 'wind' swings and the effective 'frontal area' increases - form drag is increased. If everything else stays the same, you will slow down. If you haul the nose *up* at that point you're in a world of pain.
That's precisely WHY a slip is useful - it allows a steeper descent without increasing speed (and in certain types allows you to see where you're going, but I digress) Bit like flaps really - which is why it tends to be more common practice with a/c that don't have flaps..
Miserlou, I'm afraid I disagree - you are right about the geometry, however, the angles of slip we are considering are fairly small (<30deg), minimising the geometric effect. Generally (and I'm sure there will be exceptions), the predominant effect is increased drag as the relative 'wind' swings and the effective 'frontal area' increases - form drag is increased. If everything else stays the same, you will slow down. If you haul the nose *up* at that point you're in a world of pain.
That's precisely WHY a slip is useful - it allows a steeper descent without increasing speed (and in certain types allows you to see where you're going, but I digress) Bit like flaps really - which is why it tends to be more common practice with a/c that don't have flaps..
Last edited by Mark1234; 20th Nov 2009 at 15:51.
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Mark 1234
Mark - you are correct, I left the thread after that post and just back. I should actually have inserted - 'on finals'. I am an aerobatic pilot, on taildraggers, and am fully experienced on spin/slip etc. I just do not like using it on finals, a personnal point I might add, which I thought was the subject on the original post.
I also do not think inexperienced/new PPL pilots should attempt this until full spin/slip awareness has been conducted. Should have lept incipient spin in the PPL course, however that would lead us to another thread.
I also do not think inexperienced/new PPL pilots should attempt this until full spin/slip awareness has been conducted. Should have lept incipient spin in the PPL course, however that would lead us to another thread.
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Backpacker, did you really mean to say?
You've just greatly increased the drag and if you maintain the same attitude, you'll maintain the same glide slope, but with reducing speed.
Moderator
At the risk of not honouring the indepth posts here, this is much ado about nothing. I agree with Zulu and Ratherbe. With few execptions, there is not reason to not practice sideslips, and they are no more dangerous than co-ordinated flying. If you're at risk of spinning out of a sideslip, you probably weren't that safe straight and level, and I'd worry about that first!
I completley agree with a sideslip as an element of a forced approach for glide path control, and touchdown precision. Unlike extended flaps, you can undo and redo a sideslip in an instant if you choose to.
To entertain myself, I'll sideslip right through flare and touchdown, onto the ice of a frozen lake, in my C150. When there is no wheel friction, touching down going somewhat sideways is really not a problem! The object is to touch down on lnly one wheel, go along a short distance that way, and take off again, without ever touching the other wheel down. Do not attempt on surfaces with any friction!
When you have the finer points of sideslipping mastered, you'll find that the co-ordination you command can be applied in other useful situations. One of these is getting one wheel/ski/float off the surface below takeoff speed, and before the other, to reduce surface drag. Doing that is a very slight sideslip with lots of power, and requires good control. Also useful in strong crosswind takeoffs and landings.
Most Cessna 172's are not so great to slip with flaps out (placarded), the tail does get a bit blanked, as mentioned earlier, on approach between 65 and 55 knots. Similar to the way it handles with a door off. Not a terrifying ride, but it can get your attention.
Other important reason to sideslip: In very cold air, it will allow you to carry power, and reduce the shock cooling, or over cooling the engine during long, or poorly set up approaches.
Yes there are those perfect pilots who always set up their approaches perfectly, and never need to slip or go around - and there are the rest of us!
Pilot DAR
I completley agree with a sideslip as an element of a forced approach for glide path control, and touchdown precision. Unlike extended flaps, you can undo and redo a sideslip in an instant if you choose to.
To entertain myself, I'll sideslip right through flare and touchdown, onto the ice of a frozen lake, in my C150. When there is no wheel friction, touching down going somewhat sideways is really not a problem! The object is to touch down on lnly one wheel, go along a short distance that way, and take off again, without ever touching the other wheel down. Do not attempt on surfaces with any friction!
When you have the finer points of sideslipping mastered, you'll find that the co-ordination you command can be applied in other useful situations. One of these is getting one wheel/ski/float off the surface below takeoff speed, and before the other, to reduce surface drag. Doing that is a very slight sideslip with lots of power, and requires good control. Also useful in strong crosswind takeoffs and landings.
Most Cessna 172's are not so great to slip with flaps out (placarded), the tail does get a bit blanked, as mentioned earlier, on approach between 65 and 55 knots. Similar to the way it handles with a door off. Not a terrifying ride, but it can get your attention.
Other important reason to sideslip: In very cold air, it will allow you to carry power, and reduce the shock cooling, or over cooling the engine during long, or poorly set up approaches.
Yes there are those perfect pilots who always set up their approaches perfectly, and never need to slip or go around - and there are the rest of us!
Pilot DAR
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side sliping
I am not a high hours pilot but most of those are on tail wheel "Auster's and Cub's" and i side slip, not to save a bad approach but to land off a steeper approach angle or if you have to clear high trees or wires on the thresh hold.
I have always maintained a higher than normal approach speed in a side slip, because your pitto head, in straight flight, is pointing directly into the dynamic pressure going straight in , if you are side slipping your pitto head is at an angle to the dynamic pressure so is it actually reading true air speed ? ? ?. i am not an expert but it seems to work for me.
regards Austerwobbler " "and the wobble doesnt come from side sliping either"
I have always maintained a higher than normal approach speed in a side slip, because your pitto head, in straight flight, is pointing directly into the dynamic pressure going straight in , if you are side slipping your pitto head is at an angle to the dynamic pressure so is it actually reading true air speed ? ? ?. i am not an expert but it seems to work for me.
regards Austerwobbler " "and the wobble doesnt come from side sliping either"
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While re-validating in a 152 a few years ago I got told by the instructor not to sideslip but to fly properly. I found this bizarre as it only showed his lack of comfort in light a/c. He was a jet jockey during the week. I have several thousand landings mainly on Islanders, and have slipped it just about any way possible. When operating in strong winds into short airstrips it is important to be able to slip well, at low level, to cope with rapid wind changes if you want to be able to get into the runway you are looking at. Indeed in the Islander I frequently used assymetric power to assist with the slip when countering crosswinds. Something that no-one seems to have mentioned here is that the wing down method for off setting a crosswind is itself a sideslip. My advice is simply don't do it if you are not comfortable but a sideslip is not just a method of recovering a bad approach, with practice you can fly the approach, touch down, ground roll and take off in a slip.