gibson_339 Posted June 11, 2018 Posted June 11, 2018 Hi all, first up, thoughts and prayers to all those affected by the accident at Moorabbin last week. I am not here to speculate or go into details on that particular incident, however it did get me thinking (as a relatively low time RPL pilot) about losing power on final at a built-up aerodrome and what options there are to ensure the best possible outcome. The most obvious thing to me seems to make it standard practice to effectively perform a glide approach from downwind, or turn base a lot earlier than "normal". Does anyone do this or teach this? I'm guessing it would cause problems in the circuit being in a different pattern to everybody else all the time. What other issues are there? I'm lucky to fly out at Lilydale where there are plenty of off-field options if the dreaded did happen, but i still cant help feeling sometimes when I turn base at the "correct" point (45 degrees from the threshold or thereabouts), that if i lost my engine at that point or anywhere up to final on the "correct" glidepath, it definitely wouldnt be a certainty that I'd make it back to the field, whereas if i'd just turned base earlier and set up for a glide approach, it would be a lot better situation. I'm guessing the dangers would be a much steeper approach path, possibly the chance of coming in too fast?
Birdseye Posted June 11, 2018 Posted June 11, 2018 I have never seen the point of long 3 degree final approaches with light aircraft. Not everyone is learning to fly with the aim of being an airline pilot, but that seems to be GA way.
kgwilson Posted June 11, 2018 Posted June 11, 2018 It should not matter whether you perform glide approaches all the time or used powered approaches. At any point your engine could fail so at any point you should be able to make it to the runway, the exceptions being after takeoff or touch and go where you should not turn back under 500 feet and therefore land ahead wherever possible. I was taught this in my GA training 40 years ago. The Instructor would pull the power at any point. As far as i know most still do this.
M61A1 Posted June 11, 2018 Posted June 11, 2018 How is a steeper approach path a "danger"? If you practice glide approaches where allowed it can only benefit in the long run and especially if you are flying at a strip that has limited options when the engine stops.
gibson_339 Posted June 11, 2018 Author Posted June 11, 2018 It should not matter whether you perform glide approaches all the time or used powered approaches. At any point your engine could fail so at any point you should be able to make it to the runway, the exceptions being after takeoff or touch and go where you should not turn back under 500 feet and therefore land ahead wherever possible. I was taught this in my GA training 40 years ago. The Instructor would pull the power at any point. As far as i know most still do this. My instructors have only ever really pulled the power from upwind to abeam the threshold on downwind. If we're talking about a standard by-the-book circuit, should i be able to make the field from the base turn point? Or mid-base? Or the turn to final? If I'm on the "correct" glidepath I think i would struggle unless the wind was favourable. Maybe i should be turning base earlier. I dont know. I have never actually tried a glide approach from past the abeam threshold point on downwind.
gibson_339 Posted June 11, 2018 Author Posted June 11, 2018 56 minutes ago, M61A1 said: How is a steeper approach path a "danger"? If you practice glide approaches where allowed it can only benefit in the long run and especially if you are flying at a strip that has limited options when the engine stops. I dont personally think a steep approach is dangerous, but if its not taught or practiced then it could lead to carrying in too much speed, and not setting up correctly for the landing. I'm just questioning weather the conventional traffic pattern with a standard 3 degree approach really is the best/safest option, and weather anyone here does stay high and make a "steep" approach so that they ensure they are within gliding distance for every approach (obviously subject to traffic).
IBob Posted June 11, 2018 Posted June 11, 2018 I am a low hour (and now very un-current) student. One of my instructors, an ex topdressing pilot, told me his instructor had him pull the power abreast of the threshold on the downwind leg. I did a fair few landings like this, turning in shorter and with a steeper approach, found them easier to manage and also very enjoyable. I should add this was midweeks at a country airfield (so minimal traffic complications) and one up in Tecnam (lotsa float). I have wondered if the 'standard' circuits are also something of a hangover from heavier pre-microlight flying.
M61A1 Posted June 11, 2018 Posted June 11, 2018 anyone here does stay high and make a "steep" approach so that they ensure they are within gliding distance for every approach (obviously subject to traffic). High and tight unless I'm forced to do otherwise. 1
Downunder Posted June 11, 2018 Posted June 11, 2018 I was taught RAA in ultralights to always to be within gliding distance of the strip at any point in the circuit. I do follow this. As m61a1 sad "high and tight". What makes me laugh is GA pilots/ students doing 5 mile/5 degree circuits then coming overhead to practice glide approaches.... There is something very counter intuitive to that...... How fo you KNOW when the engine will fail?
winsor68 Posted June 11, 2018 Posted June 11, 2018 My instructors have only ever really pulled the power from upwind to abeam the threshold on downwind. If we're talking about a standard by-the-book circuit, should i be able to make the field from the base turn point? Or mid-base? Or the turn to final? If I'm on the "correct" glidepath I think i would struggle unless the wind was favourable. Maybe i should be turning base earlier. I dont know. I have never actually tried a glide approach from past the abeam threshold point on downwind. There is no guarantee you will or should make the field from anywhere. 1
pmccarthy Posted June 11, 2018 Posted June 11, 2018 It’s a good idea if you can fly a tight circuit. I try to, but often need power anyway. On my last AFR I made one successful glide approach but only after a go around on the previous attempt when I would have gone through the fence.
skippydiesel Posted June 11, 2018 Posted June 11, 2018 It should not matter whether you perform glide approaches all the time or used powered approaches. At any point your engine could fail so at any point you should be able to make it to the runway, the exceptions being after takeoff or touch and go where you should not turn back under 500 feet and therefore land ahead wherever possible. I was taught this in my GA training 40 years ago. The Instructor would pull the power at any point. As far as i know most still do this. Just being picky I know but quoting absolutes like "500 ft" is not helpful - I would humbly suggest know your aircraft ie what it & you can/not do in the prevailing weather/wind conditions.. On a long past BFR, my instructor, on climb out from the strip, (in my Zephyr) declarer an engine out at under 500ft and was amazed that I was able to make it back to the strip and achieve a down wind landing. I would not have attempted this in any of the small Cessna's I did my original GA training in - this would have been a near straight ahead off field landing scenario.
skippydiesel Posted June 11, 2018 Posted June 11, 2018 When I did my GA to RAA conversion training (in Jabiru's) my instructors used what I call the " step" glide approach on final. The idea is to to come in at a steeper decent angle and faster than you would on a constant glide path/gradient (the GA way), aiming for a touch down point just short of the threshold. When you know you have the runway "made" reduce speed/raise the nose and re aim for a touch down on the or just after the threshold. The whole idea is to maintain/conserve energy, so that in the event of an engine out, you still have the momentum/glide path to make the runway. Works well but takes a little getting used to after GA brainwashing.
gibson_339 Posted June 11, 2018 Author Posted June 11, 2018 When I did my GA to RAA conversion training (in Jabiru's) my instructors used what I call the " step" glide approach on final.The idea is to to come in at a steeper decent angle and faster than you would on a constant glide path/gradient (the GA way), aiming for a touch down point just short of the threshold. When you know you have the runway "made" reduce speed/raise the nose and re aim for a touch down on the or just after the threshold. The whole idea is to maintain/conserve energy, so that in the event of an engine out, you still have the momentum/glide path to make the runway. Works well but takes a little getting used to after GA brainwashing. The space shuttle approach, minus the MLS
BirdDog Posted June 11, 2018 Posted June 11, 2018 Hmm... Interesting read. I was taught by a very experienced instructor, and we practiced the crap out of glide approach. In fact, I setup for it on every landing now. Recently I have been surprised at how little is being taught to new pilots, as I was put through the ringer. We practiced engine outs every where. Take off, in the circuit, over the coast, in the middle of nowhere etc etc. I good deal of attention was given to things like side slip , and how to get down quickly if running out of room etc. Forced landings were practiced heavily away from the airfield. Short field and soft field landings etc, and then mixed it up with simulated engine failures with a short field, then a soft field etc etc etc. We called it "how not to die training" Most of my landings are now all glide, with only a very occasional need for power if I have hit a good head wind on final. But a good look at the windsock and I can generally pre-empt that. I also spend about 2 hours every 3 months or so going over emergency sequences again. Forced landings, stall recoveries, side slips, soft and short fields - the whole box and dice. I own the bird so the costs are low, and I like to keep my skills up, instead of just take off, cruise and land. 1
turboplanner Posted June 11, 2018 Posted June 11, 2018 When I did my GA to RAA conversion training (in Jabiru's) my instructors used what I call the " step" glide approach on final.The idea is to to come in at a steeper decent angle and faster than you would on a constant glide path/gradient (the GA way), aiming for a touch down point just short of the threshold. When you know you have the runway "made" reduce speed/raise the nose and re aim for a touch down on the or just after the threshold. The whole idea is to maintain/conserve energy, so that in the event of an engine out, you still have the momentum/glide path to make the runway. Works well but takes a little getting used to after GA brainwashing. (Edited..mod)... GA flying involves quite a different type of aircraft( ...edited..mod)
Cosmick Posted June 11, 2018 Posted June 11, 2018 Just saying. Flew Brisbane to Newcastle Jetstar A320. Joined Downwind, Height felt under 2000, Turned Base and Final in a reasonablly tight circuit. Unreal turning that close to the ground.
BlurE Posted June 11, 2018 Posted June 11, 2018 Funny, I am just messing around in some GA stuff for the first time. After many years an many hundreds of RAA landings using "pitch for speed - power for height" I am now trying to learn "power for speed, pitch for aim point" I and finding it very counter intuitive - especially on a practice glide approach where you don't have power and have to switch back to pitch for speed anyway. I accept that heavier GA is different but a ''152 just feels like a more solid Tecnam. My point is that if GA training teaches you to use power for speed on a standard approach I could well see you being caught short if the fan stops. Personally I really like glide approaches and see them as a fun exercise in energy management.
M61A1 Posted June 12, 2018 Posted June 12, 2018 Funny, I am just messing around in some GA stuff for the first time. After many years an many hundreds of RAA landings using "pitch for speed - power for height" I am now trying to learn "power for speed, pitch for aim point" I and finding it very counter intuitive - especially on a practice glide approach where you don't have power and have to switch back to pitch for speed anyway. I accept that heavier GA is different but a ''152 just feels like a more solid Tecnam. My point is that if GA training teaches you to use power for speed on a standard approach I could well see you being caught short if the fan stops. Personally I really like glide approaches and see them as a fun exercise in energy management. I have flown with several very experienced instructors that also instruct GA, and all of them teach pitch controls speed. Besides being a "fun" exercise, it's also a very useful skill to have.
skippydiesel Posted June 12, 2018 Posted June 12, 2018 - water cooled pull the throttle and glide - yes can be done - air cooled - some power to stop shock cooling - don't know about air cooled much anymore Hi John, Once again being "picky" please forgive - I was always taught, whenever possible, to reduce power gradually (land/sea & air). This allows for a more progressive cooling of the engine,. It should not matter how your engine is cooled if this is your normal practice. All engines can be brought back to idle. On a long decent (particularly if carb ice conditions are suspected) it is a good idea to maintain additional power principally to reduce the chances of ice formation and even increase power in a burst to check for icing while you still have sufficient hight to make plans.
BirdDog Posted June 12, 2018 Posted June 12, 2018 I am with Skippy, If I am up high, my top of descent into the airfield is a long way out so that I can descend with power, and with Carb Heat. Then after the flyover and windsock etc etc, I join the circuit at about 70-80kts with a full fine prop which brings my RPM down a bit. keeps the engine warm, but not working its nuts off. Back to idle at the base turn - Carb Heat off on final (once I am certain of making the field) Just my way of doing things though.
facthunter Posted June 12, 2018 Posted June 12, 2018 Both pitch and power affect speed. It's not ONE or the OTHER exclusively. same as on the approach using crab or wing down, where you should use what is most appropriate, which can be "both".. If the donk's not working you have only pitch left. When in a place like Moorabbin. I wouldn't try anything too "unusual" from any point in the circuit, as a general principal unless you have the place to your self.. Power gives you more control over your approach and landing touchdown point. You have more chance of being at the right height and speed as you land, using power for adjustments.. IF you are" engine out" you should plan to land further in, to cover the situation where you get a bit less lift or more headwind than you expected . You are better to hit the far fence at walking speed than the near one at flying speed +. is the logic there. It's always better to land while you have some power still available in any given situation. . A motor on say 20% power is probably less likely to fail than at any other time when you are in the air. It's lightly loaded but maintains some heat. An idling motor, if used for an extended period particularly, may cool down and not respond quickly to a go around power application, IF required. Some motors are not particularly reliable when idled . You do an idle check when taxiing out at all times don't you.? . Of course.. It IS important. Practicing glide approaches is not a bad idea either. It familiarizes you with that aspect of your plane's performance. It was commonly taught as "normal" for low inertia high drag U/L's but often gives a very steep approach, particularly with any sort of headwind. You can often get a relatively high sink rate as well which needs a bit of excess speed to enable a reliable flare to be guaranteed.. I always tend to keep circuits tight but if the other user's aren't doing the same , you have your hands tied, so to speak.. The most likely situation for an engine failure is on take off, when most things are more critical and the engine is delivering FULL power. Nev
M61A1 Posted June 12, 2018 Posted June 12, 2018 Both pitch and power affect speed. It's not ONE or the OTHER exclusively. Some glider pilots might argue that point..... 1
skippydiesel Posted June 12, 2018 Posted June 12, 2018 I am with Skippy,If I am up high, my top of descent into the airfield is a long way out so that I can descend with power, and with Carb Heat. Then after the flyover and windsock etc etc, I join the circuit at about 70-80kts with a full fine prop which brings my RPM down a bit. keeps the engine warm, but not working its nuts off. Back to idle at the base turn - Carb Heat off on final (once I am certain of making the field) Just my way of doing things though. Sounds good to me BD - Years ago I did a little bit of flying in Canada. As I was not familiar with The Okanagan Valley area, I elected to have an instructor go with me, with my two young sons in the back. On returning for landing and starting my decent, my young instructor basically ordered me to power up again and then use carbi heat befor reducing power. The carbi heat was maintained all the way down to touch-down. We discussed this (new to me) technique in the club house. Canadians are paranoid (as you might expect) about ice formation, don't bother with assessing its likely hood, just assume it will happen. We in Au get a bit blase about carbi ice and tend to only use heat on down wind, base and close it on final. I was taught to do this - the argument being that there is a power loss with turning on carbi heat that should be corrected befor touch down, in case of a go round. When you think of it, the power reduction is minimal, compared with an ice choked carburettor, so why not keep the heat on, at least until on the ground. I adopted the Canadian way - cheap insurance.
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