cficare Posted December 4, 2011 Posted December 4, 2011 Been flying with a few students/pilots lately.... Sometimes they are a bit quick on final....I say "your going a bit fast" (or something to that effect)..they pull the throttle to idle. Is it me or is the response wrong?? 1
Guest DavidH10 Posted December 4, 2011 Posted December 4, 2011 The response is wrong, but probably due to lack of prior knowledge.. Is this before they have understood the primary and secondary effects of controls and the fundamentals of lift /weight, thrust / drag? ... or was it a configuration change that was lacking? People are programmed by their use of ground based conveyances that the speed is a function of accelerator / brake. They probably don't even consider, in the first instance, hills.
cficare Posted December 4, 2011 Author Posted December 4, 2011 Its really interesting David... I think there is a fundimental flaw in their 'fundimentals'!! We need to emphasis that 'attitude' controls speed...at any power setting.
djpacro Posted December 4, 2011 Posted December 4, 2011 He was probably taught http://www.jacobsonflare.com/downloads/2. The Jacobson Flare CASA 1997 Flight Safety Seminar Series Notes Pages accompanying Presentation.pdf
cficare Posted December 4, 2011 Author Posted December 4, 2011 that scares me....i've been in the situation where that was 'the' method ...introduced by an incoming CFI...it completely confused a class of 20 for a couple of months.... until he was 'replaced'..................
Powerin Posted December 4, 2011 Posted December 4, 2011 With the reading I did before learning to fly (and testing with a flightsim) I guess I have always treated airspeed as a function of angle-of-attack in that a certain AoA tends to produce a certain airspeed. Elevators control AoA and trim sets the elevators. So from the start I've trimmed for airspeed (or more accurately trimmed for AoA) and had a reasonably stable approach speed set up before turning final (if I don't stuff it up). My instructor has never told me to do it differently. Thinking about it I guess I use a combination of attitude and power to get me where I want to be at the right airspeed on final, but attitude comes first usually. The majority of my approaches are glide (which is my instructor's preference) so I don't usually have the option of pulling to idle. More flaps, sideslipping or going around are the options if I'm ever coming in hot. I'm still a student, so I suspect what I do works OK for the aircraft I fly, but won't necessarily translate to another type. 2
Guest avi8tr Posted December 4, 2011 Posted December 4, 2011 It might be the wrong response but it is common to have on too much power on final when you are low hours and reducing the power often helps. I take it that you didn't teach these students in their early stages? Perhaps it wasn't explained well enough to them at first? General principle though in cars boats and anything that runs on fossil fuels is to reduce the throttle to slow down! Fossil Fuels - Using the past to power the future!
Wayne T Mathews Posted December 4, 2011 Posted December 4, 2011 I take it that you didn't teach these students in their early stages? Perhaps it wasn't explained well enough to them at first? General principle though in cars boats and anything that runs on fossil fuels is to reduce the throttle to slow down!Fossil Fuels - Using the past to power the future! There's been a lot said over the years about using power versus attitude to control airspeed on approach. Both techniques have their place and their advocates. But to make it simple for my abinitio students, I teach them to close the throttle on base and land with power off. My reasoning for that is that if/when the engine quits on them one day, they'll revert to what they were first taught and they'll control their airspeed with attitude.
Scotty 1 Posted December 5, 2011 Posted December 5, 2011 I teach them to close the throttle on base and land with power off. My reasoning for that is that if/when the engine quits on them one day, they'll revert to what they were first taught and they'll control their airspeed with attitude. Thats the way I was taught in the trike. Latter on in training in 3axis the FI turned the noise off on engine out training and all was good, I didn't panic and went straight back to the glide approach. That works for me. My trike instructor explained to me the same thoughts as Wayne. Cheers Scotty 1
Guest DWB Posted December 5, 2011 Posted December 5, 2011 I teach them to close the throttle on base and land with power off. I would think most if not all ultralight pilots have been taught this method for the reasons stated above. I have since self taught myself powered landings, because they do have their place sometimes. I quickly adapted to mostly powered landings on my own strip as a means of guaranteeing I got down under the power lines, although after several hundred landings here now I can do it with a glide approach, however I've had them turn into go-arounds because if I'm not at a certain height at a certain spot in the landing phase I call it off. I think we should all have various techniques in our kit bags & should be taught all. Another that I use, which I call "dropping it in" & it may well have some other name, which I also taught myself, at 5000' initially, is for when I need to land over the power lines on the northern end of my strip. If I try to land normal approach going over the lines this places my aiming point too far down the strip at the same time maintaining good clearance of the lines & unable to pull up in time before end of strip. So I set up well back on long final straight & level with power to maintain, stage 2 flap, 55 knots, at approx 6 metres above height of power lines, when the lines pass under the nose I close the throttle, the nose drops quickly, speed is maintained at 55kn or may increase a little towards 60kn, then round out, flare & land & finish up with heaps of room to stop. Sometimes I might pull on stage 3 flaps just before I pull the throttle depending on wind etc. Now the important bit. I AM NOT AN INSTRUCTOR. Always ask your instructor to help you master different skills. There is inherent danger in landing over power lines (& trees or any other obstacle for that matter) particularly on shortish strips.
Spin Posted December 5, 2011 Posted December 5, 2011 Going back to CFI's original question, I think I'd answer "probably yes - but not necessarily" - reason being that I am wary of one size fits all solutions in aviation. I'm not an instructor, nor do I have many thousands of hours behind me, but I have had the advantage of flying with many different instructors from ultralight, military, GA and airline backgrounds over the 20 odd years that I've been around aircraft and if nothing else, I've seen that there is frequently more than one way to exfoliate the proverbial feline. Early on in the training, sticking to the attitude for speed is valid I believe but as a student progresses to short field landings, ie flying behind the drag curve in most aircraft on approach, a more subtle combination of methods will probably be called for. I was rather surprised to be pulled up in a recent flight for raising the nose to lose speed - but then the instructor does drive vast chunks of Airbus branded aluminium in his day time job and I believe that method is expected of them in that environment. 1
Guest aviatrix27 Posted December 5, 2011 Posted December 5, 2011 bearing in mind I'm a GA pilot, so my mileage might vary... I was taught to trim to a speed (eg in my Grumman, 70 knots), then adjust power as necessary, keeping the air speed the same. Typically, if we were using RWY 18 where I did most of my early training, we would get lift from the freeway, immediately followed by sink from the soggy paddock before the RWY. Always had to adjust the throttle, but kept speed around the same until flare.
Guest DavidH10 Posted December 5, 2011 Posted December 5, 2011 Just to add a contrast... I was taught, and always perform powered approaches unless practising a glide approach. I mostly use AoA to adjust speed and power to adjust for varying lift or sink encountered on final. I say mostly, because I do what is needed to achieve the desired result under the specific circumstances. I've also been performing formation landings where the descent rate and speed is set by "lead", but aiming point and a precision touchdown are critical to avoiding lead's wake turbulence. A glide approach under this circumstance is not appropriate. Responding to the document that DJP linked, trying to use a point on the windscreen as an aiming guide was something I tried in my early training, but soon dropped in favour of the calibrated eye (observing relative movements). In a trike, the pod and thus windscreen attitude is affected by whether there is 1 or 2 POB, how much fuel is on board and how much the gusts are banging the pod around. Using a mark on the windscreen is likely to result in pilot induced oscillation. That said, it was helpful to me in calm conditions for the first few hours of circuits, during my training so that I could get the sight picture embedded in my brain. Where I fly, it is unusual in summer not to encounter both lift and sink of varying degrees on final. From time to time there can also be wind shear. Two GA aircraft, the other day landed downwind because the wind at circuit height was in nearly the opposite direction to that at ground level. I don't know whether that was intentional on their part, but their aircraft were well capable of handling the downwind landing. After they had cleared the runway, I landed into the wind (on the reciprocal runway). *I'm not an instructor, so I'm not advocating or providing any specific techniques or advice. Ask your instructor.
Guest aviatrix27 Posted December 5, 2011 Posted December 5, 2011 :p Yarrawonga on Saturday was a bit all-over-the-place when it came to wind! I'm sure I landed on 01 and departed 3 hours later on 19 (but my memory could be off). When landing on 19 there, I always encounter lots of sink on late final. I had head winds all weekend (Mansfield to Yarrawonga to Ballarat Saturday, then Ballarat to Mansfield Sunday) - unusual for me, I normally get tailwinds. Oh well, had to happen some time, I guess.
Guest DavidH10 Posted December 5, 2011 Posted December 5, 2011 :p Yarrawonga on Saturday was a bit all-over-the-place when it came to wind! I'm sure I landed on 01 and departed 3 hours later on 19 (but my memory could be off). When landing on 19 there, I always encounter lots of sink on late final. I had head winds all weekend (Mansfield to Yarrawonga to Ballarat Saturday, then Ballarat to Mansfield Sunday) - unusual for me, I normally get tailwinds. Oh well, had to happen some time, I guess. Sorry I missed meeting you. Was on a shopping expedition on Saturday and by the time I got out to the AD in the evening, it wasn't worth pulling 4 acft out to get mine. The wind had settled some by then. Your comment about rwy 19 is pretty spot on and also similar on 23. In summary, Canola sucks! I'm envious that you always get tail winds. ;)
Guest aviatrix27 Posted December 5, 2011 Posted December 5, 2011 I'm there frequently, will try to remember to PM you when I'm going to be there again
Guest aviatrix27 Posted December 5, 2011 Posted December 5, 2011 I'm there frequently, will try to remember to PM you when I'm going to be there again
David Isaac Posted December 5, 2011 Posted December 5, 2011 This has always been a 'hotly' debated issue. In answer to CFi's first question provided the student was not too fast and too high, I would advise to raise the nose to lower the speed as a first reaction and then use the power to adjust the rate of descent. If however the student was too fast and too high, I would raise the nose and pull the power back and if in a C150 as an example and having all the flap out as well you can lower the nose to the maximum white arch speed and lose height effectively and then when you raise the nose to lose the excess speed she will slow rapidly due the high drag of 40 degrees of flap. Back to the topic, if I cast my mind back, I was taught glide approaches from the start (1970 for me) with flap application in a Morane Salnier Rallye type MS880B (hows that for pointless memory). I was then taught glide without flap and then the normal (for GA) powered approach followed by 'short field' technique which I typically use all the time because you can spot land with more control, but if the fan stops you probably wont make it in. I was always taught attitude determines speed and power controls the rate of descent. Short field techniques prove that concept well. This technique does not work well in large heavy aircraft and they simply point to the landing spot and vary speed with power. Neither am I an instructor so take what I say for what it is worth. 1
jetinight Posted December 11, 2011 Posted December 11, 2011 Hey Aviatrix27, I've been away for a while with moving, computer connection trouble and a whole host of other problems, but I back again. I Hope you & family are all safe & well. Anyway, take care, God Bless.
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