Jump to content

do you use a Glide or Power approach??


Tomo

Recommended Posts

Just interested to hear what others do for there approaches...

 

My instructor teaches the glide approach (engine on idle), so if your engine quits it doesn't really matter (as much)... and I thought that was the proper way to do it, (because it makes sense), but I've seen a lot of power on approaches recently and so that's how this question came too...

 

Thanks,

 

 

Link to comment
Share on other sites

  • Replies 56
  • Created
  • Last Reply

Top Posters In This Topic

Guest Brett Campany

60kts all the way in depending on the cross wind of the day, add 5kts or so. Throttle to idle over the piano keys and have that power just in case you need to increase power on touchdown or need to go around.

 

 

Link to comment
Share on other sites

Guest Cloudsuck

I believe that all pilots should be taught both. The glide is hammered into us for a good reason so that our brain image is in gear for a FLWOP.

 

 

What I do see in RA is that most are only ever taught to glide approach. The question therefore is this... Is you instructor teaching you short field approaches? The correct and safer method of short field approach is a powered approach.

 

 

Perhaps they are not teaching short field as most ultralights land pretty short anyway. It is a pitty as it can be a very useful skill on occasion.

 

 

Link to comment
Share on other sites

Perhaps they are not teaching short field as most ultralights land pretty short anyway. It is a pitty as it can be a very useful skill on occasion.

Yeah I'm taught power on as well for short fields, etc... He's a glider instructor as well, so good judgment of where you think you will touch down is being drummed into me...:thumb_up:

 

It's just that, today watching a few planes cruise around in Toowoomba, some fella's have this huge long downwind and then once on finals there off and on the throttle to keep the speed/hight under control (GA fella's:laugh:) It was just interesting to see the way different people do things...

 

 

Link to comment
Share on other sites

Guest drizzt1978

Yeah I was luck enough to learn both. I always use a little bit of power after I learnt the benefits. For me it Feels a lot more "on track" when there is a bit of wind around, and seem to be less adjustment. Like to land just on 1400 rpm in the J170. Also i find the landing is more positive just fly it in, put it on then power to idle.

 

 

Link to comment
Share on other sites

Glide approach.

 

I actually believed for quite some time that if I had to add power, I'd stuffed up the approach and was in line for a kick up the ring by my instructor. He just thought that I was weird because I swore if I had to add power....

 

 

Link to comment
Share on other sites

Unless there is good reason for powered approach such as conditions, etc, I can't see the point. All one is doing is adding risk by relying on something that can fail.

 

If glide approaches are your regular thing then an engine quitting during the landing phase isn't really going to raise an eyebrow. Added to that, getting used to the peace and quiet during landings also makes the eventual forced landing more of a non-event. Trust me......

 

 

Link to comment
Share on other sites

I Probably use a mix of both - i was up in some pretty wild xwinds yesterday, and because the plane was set up in a draggy configuration i.e almost full right aileron and full left rudder, i had to have a fair bit more juice on the approach than usual..

 

I always liked that old book "stick and rudder" where he talks about throttle being all about the up and down, and stick forward and back being about speed..Seems to be the case..But i guess thats why circuits are the size they are, so that if something goes astray we can hopefully make it back unpowered....

 

 

Link to comment
Share on other sites

Guest Brett Campany

I think I'd rather see people use the power they have to bring an aircraft down. Everyone's trained in glide approaches but I also think everyone's expecting the engine to cut out. It's always good to have that in the back of your mind but personally I'll always use a powered approach because the power is there.

 

That's just my 2c though.

 

 

Link to comment
Share on other sites

As most of you seem to do glide approaches, I thought I'd explain (from a GA perspective) some advantages of powered approaches.

 

Firstly, remember that airflow over the control surfaces will be greater when you have power on. That means more effective controls when you need them most - close to the ground. The last thing I want is less responsive controls if I encounter wake turbulence or a decent crosswind.

 

Also remember the stall speed decreases when you have power on, resulting in a greater safety margin and/or a lower possible approach speed. This means short field performance.

 

There's that old saying that power and attitude = performance. If you take out the power, that only leaves you with attitude to play with.

 

Using power you can lessen the rate of descent, resulting in less of an "arrival", especially in turbulence. (Helicopters can use a lot of power to land!) From a GA perspective, the heavier the aircraft you end up flying, the more important you may find this. The heavier ones do tend to sink when the power comes off and often the power is left on into the flare, or a bit of power is added at that time.

 

If you decide you one day want to take your flying a bit further and do an instrument rating, the rate of descent and approach path requirements will mean you would need to set up the aircraft at a particular rate of descent, which you can't do on a glide approach.

 

If you want to take that idea further, think of airline aircraft - they use powered approaches. Turbine engines take a while to spool up too, so pilots of turboprops and jets don't want to get too low on power on approach.

 

As for GA piston engines, the cooling aspect of going to idle isn't great for them, which is why glider tug pilots don't tend to pull the power after release, they tend to pull into a descending turn and keep the power on to avoid shock cooling the engine. I'm talking about GA engines here, I can't offer advice on some of the engines you may be using!

 

So there are a few points on why power can be useful. As I said, I'm talking about GA so take advice from your instructor and do whatever works for you!

 

 

Link to comment
Share on other sites

Power on approach.

 

If the motor is on the idle stop, it is more likely to die than if a little power is left on and taken off at or just before the flare. Engines tend to fail at high power, or stall at idle. ( Especially these Bing CV's that pull against a spring to close). Incidently the engines idle is meant to be tested prior to take off. Do you all do this? If the motor stops you are meant to have it serviced. Then there is the problem of a high idle speed causing extended float in some "clean" designs.

 

Flying in turbulence (during the approach) . You are making it MUCH MORE difficult if you don't use power. You have much less control of speed and approach path, (and height over the fence if the strip is short.)

 

Sink rate. Power off sink rate in a Gazelle for instance, is around 800 fpm at times . Far too high for safe roundout.

 

Another thing that concerns me, is that with the ability to glide to land ON THE FIELD being drummed into you, this could be a factor in the Return to the Field decision when the engine fails on TO. It is common to hear things expressed like" I don't know why I did that. I have been told thousands of times NOT to turn BACK", but I did. Unfortunately it has been a big killer, so not everybody gets a chance to speculate on why they did it.

 

The power off approach went out the window in GA around 1963, and the powered approach became standardardised. I don't like this either, so I strongly recommend practicing BOTH techniques and using the APPROPRIATE one depending on the circumstances. Regards Nev.

 

 

Link to comment
Share on other sites

I tend to use a power on approach with my Thruster which has a R582. My reason for this particually during circuits or after a long climb is that going back to idle the engine cools down very quickly. Next time you do a glide approach take a look water temp on downwind and then when your on the ground. I always do a couple of glide approaches first to make sure I have my eye in but from then on I try to look after that Two Stroke as much as I can!

 

Adam.

 

 

Link to comment
Share on other sites

Guest pedrok

I had to think a bit and reread my manuals before I considered adding my response :)

 

But isn't every aircraft and field going to be a bit different: brief examples from my limited GA perspective:

 

  • Ultralights can fly a lower circuit, so they are starting a bit lower anyway
     
     
  • You are meant to be to on final at least 500m or more from aerodrome boundary, so it really depends on your aircraft's stated gliding range.
     
     
  • I was taught to fly a shorter downwind and steeper approach for Glide approach and/or not to use too much flap until certain that you will make the strip, then you do for a normal approach
     
     
  • When flying with other traffic in the circuit you should try and conform to a standard circuit - unless you tell everyone you are doing something different. I have found at Bankstown that you need to vary your circuit speed so that you maintain a suitable distance from they guys ahead.
     
     
  • When I was flying at Hoxton, warm days generally meant you could expect a bit of up and down sink on finals as you crossed the paddocks, golf range, freeway, so you needed to adjust power a bit.
     
     
  • If starting a glide approach - (pulling off the revs when before turning base) it is going to be a while before you land, so icing is a concern. In PFLs I think I probably add power between 1-3 times in that period. I think the plan that crash landed near Camden a few months back was practicing PFLs and didnt use carby heat or cycle the throttle - so when he needed power it wasn't there. I know I want power available immediately on finals just to counter drafts, unexpected events and be ready to go-around.
     
     
  • I haven't been taught to use glide approach as a norm, so I suppose I prefer to keep Normal Landings normal, and to practice PFLs completely - eg to my Emerg checks, paxbrief, calls as a separate and complete exercise
     
     

 

So Im guessing everyone is going to be different because of the aircraft, strip, weather conditions, experience and method of instruction is going to be different

 

 

Link to comment
Share on other sites

Guest brentc

As stated earlier, shock cooling of the engine is a concern especially for a longer approach. If you idle it in for the approach, then power away for your circuit you're delivering full power on an essentially cold engine, thus increasing wear and tear. Whilst the actual detriment to the engine may be unmeasurable, it makes perfect sense. Not so bad in a Rotax engine such as the 912 as they are also water cooled, however not brilliant in a Jabiru.

 

 

Link to comment
Share on other sites

Guest Evan Cameron

I would like to add to Masda's coments on powered aproach. Coming from G A , we were taught both,but you definetly need power on at controlled airfields as you need to fit in the circuit where told. I landed at Auckland International a number of years ago in a C-172 and had to extend out for wake turbulance behind a twin engine jet then fight my way back on finals under full power to a flapless landing of 90 knots ( minimum speed allowed incircuit at Auckland.) When converting to RAA, I was told that power off was the norm but I always use power on aproach as Masda said, better controll of aircraft. Cheers Evan.

 

 

Link to comment
Share on other sites

  • If starting a glide approach - (pulling off the revs when before turning base) it is going to be a while before you land, so icing is a concern. In PFLs I think I probably add power between 1-3 times in that period. I think the plan that crash landed near Camden a few months back was practicing PFLs and did use carby heat or cycle the throttle - so when he needed power it wasn't there. I know I want power available immediately on finals just to counter drafts, unexpected events and be ready to go-around.
     
     

 

 

I don't know a lot about this sort of thing:confused:, but I thought carb ice would be more likely to form with power on due to more vacuum in the throttle body.

 

Am I wrong about this ?

 

Regards Bill

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

×
×
  • Create New...