Landing Tips

[Simon Lumsdon 1]

Just maidened an old Mustang ARTF (jamara spirt of America) with a 90 asp fs which flew beautifully, not overpowered but really steady and enjoyable. BUT my landings were dreadful, i tried to wheel it in but it ended up pitching down and breaking the ridiculously weak undercarriage. I can do a nice slow approach over the field boundary but dont seem to be able to judge the elevator control to land her horizontal, seems to touch down slightly nose down at which point it digs in? CG and wheel position is fine, its pilot error. Most of my landings take half the strip to get the height/position right, then a good landing but run the danger of running out of room. What am i doing wrong?

 

Need some advice on landings pls 

 

many thanks

 

simon
 

 

[Brian Cooper]

Most warbirds appreciate being "flown" down to the ground. 

In other words, they don't like being left to glide down.

 

* Elevators control the speed. . The power controls the height.

As soon as elevator is applied prior to touchdown, the model slows down. . At touchdown there can sometimes be insufficient speed (momentum) left to roll on the wheels. . Let's call it "close to the stall" so it digs in and noses over. 

 

Use some power to flare out with. . Fly it  onto the ground. 

It's a careful - and gentle - balance of elevator and power.

 

Have fun. 

[Simon Lumsdon 1]

Thanks Brian, i know how to use throttle for height but think i am too scared of stalling to use the elevator for speed, need to practise this

[leccyflyer]

Excellent tips Brian.

 

For me a well executed landing is the best feeling in model flying and doing a good one brings immense satisfaction. Wheras not doing a good one and the ignominy of a "flip" is very frustrating. I liken it to the difference between the majority of golf shots and that rare one where the club contacts the ball in the perfect spot and you simultaneously feel and hear that it's going to be perfect.  It's also the one bit of your flight that there is certain to be someone, somewhere, watching and a particularly nice landing can generate a spontaneous round of applause from fellow fliers. Brilliant stuff.

[Nigel R]

Brian has fine advice in his post. Just a little extra speed can work wonders - it doesn't need much to increase elevator authority at the key moment - don't be afraid to feed in a dab of power, to control the rate of descent at the critical moment and to help with flare out.

 

[Simon Burch 1]

1 hour ago, Simon Lumsdon 1 said:

I can do a nice slow approach over the field boundary but dont seem to be able to judge the elevator control to land her horizontal, seems to touch down slightly nose down at which point it digs in?

 

23 minutes ago, Simon Lumsdon 1 said:

i am too scared of stalling

 

Just a thought - for most aeroplanes, the touchdown attitude should be slightly nose-up.  I wonder whether your fear of stalling at low-level is subconsciously preventing you from applying the requisite amount of up-elevator just prior to touchdown.

 

Do you have any experienced flyers who could try the model out for you?  That way, you'll be able to tell whether the fault lies with your flying or the model's set-up.

Edited October 10 by Simon Burch 1

[Martin Harris - Moderator]

Some good points above.
 

Primarily, the elevator controls the angle of attack and airspeed is the result of the combination of this and thrust balancing forces.  Generally, the slowest possible airspeed is obtained at full throttle!

 

Speed over the ground is meaningless - what counts is angle of attack and the simplest guide for us is the model’s attitude (and I don’t mean whether it’s a mean so and so, waiting to bite the pilot!) and maintaining this is the job of the elevator while the approach slope is controlled by throttle.  Keep the nose attitude correct and it wont stall. The exception to this is sharp edged gusts caused by turbulence, which is why you should fly a faster (slightly more nose down) approach in windy weather. 
 

One tip that may help is nothing to do with approach speed.  I believe very few pilots consciously appreciate the effect of standing a few feet from the runway on the visual perception of when to make the final turn.  This results in turning too early and the result is a continuously curving flight path to compensate.  Maybe not too bad for a scale Spitfire approach but it results in additional workload, detracting from fine control of the glide (slightly misleading term) path.  Completing the final turn a little past where it appears correct will actually align the model with the runway and allow more of a side on view in the critical stages, allowing better judgment of attitude and a model which never flies directly towards you. 

[Simon Lumsdon 1]

Thanks all and thanks Martin, some great points here. I can certainly fly my Panics nose into the sky along the field and get the point being made.

 

One observation is our field orientation means the plan is usually point towards the pilot on landing so dont get that side perspective, maybe i should bring the model closer in and practise a more nose up approach. I think i generally let models sink/glide in which means a fast landing and running out of room. Starting to realise i need to fly them in, will try some nose up slow passes perhaps

[Martin Harris - Moderator]

I don’t expect you’ll need the advice to experiment at a reasonable height, but exploring low speed handling is a great idea. 
 

One example springs to mind.  A clubmate had a heavy Shoestring racer with an engine which he insisted on having a high idle speed and with a high pitch propeller - 14” comes to mind… 
 

He asked me to land it for him as he kept overshooting.  I managed to just get it in on a longer diagonal runway but explained that it would probably benefit from a high drag/power approach although as fuel was getting low, I hadn’t had time to experiment with its handling.  He asked me to demonstrate/experiment at his risk so once I’d checked it’s low speed handling, I did a number of approaches  on the shorter runway at progressively higher angles of attack/power onto our shorter runway. 
 

Encouraged to “go for it” by the owner, the last approach was at what looked an extreme nose up attitude but still perfectly controllable and the model was on the ground and stopped well before using half the available runway. 
 

Good luck!

[Dale Bradly]

I believe that putting the wheels on the ground is easy.

The hard part of landing is about 300 ft or more out.

The approach is what makes and breaks a landing. There is a reason many full-size aircraft perform some form of circuit.

Ensure you are practicing and working on your approach. Be at the correct speed and height way out there. When that goes right, finals and touchdown just flow on from there.

[Cuban8]

1 hour ago, Simon Lumsdon 1 said:

Thanks Brian, i know how to use throttle for height but think i am too scared of stalling to use the elevator for speed, need to practise this

Ditto all the previous comments.

 

I'm certainly no expert and find landings the most challenging of all the manouvres even after being at this hobby for over fifty years. 

For what they're worth, a few tips that I've been given oven the years and discovered myself by sheer persistence......

 

Don't have too much height on finals...

 

Don't lose airspeed and wind up dragging the model in.....

 

A good and reliable slow running and idle on an IC engine is a big help.....

 

Landing off a curved approach is much easier with warbirds and heavier models in general....

 

Don't have too much elevator movement available and avoid expo on the elevator if at all possible....

 

If you've got the room, don't land! Hold off the last foot or less and let the model do its stuff.

 

Adapt technique to the model being flown - no one size fits all.

 

Good luck.

Edited October 10 by Cuban8

[Don Fry]

Of course, boring, and take very great care every time, or you break it. You need a beer mat. Put it on the landing area, where you want to touch down. 
Do half a dozen circuit low passes/landing approaches, at landing speed, say finishing at  50 cm altitude, above the beermat. Every flight. Not at the end, you are tired then. 

[Andy Gates]

If you are having approach direction / lining up issues, take a moment when no one is flying - stand in the centre of the runway and look at the horizon in both directions for features that align with the centre of the ends of the runway.

You can use these features to assist in lining your model up.

Far too many final turns are far to early meaning realignment of the model.

Get it right and your work load drops drastically on finals meaning a better landing.

 

[Martin Harris - Moderator]

That’s exactly how I try to explain it to pupils. They are usually very surprised how far that feature moves in the few yards as they walk back to the flight line. 

[Jon H]

On 10/10/2024 at 08:56, Simon Lumsdon 1 said:

Thanks Brian, i know how to use throttle for height but think i am too scared of stalling to use the elevator for speed, need to practise this

 

You can make like easier with an elevator-flap mix. Even if the model has no flaps, you can set up this mix to retrim the model for landing. 

 

In the case of the 30-50cc class models i fly, dropping the gear and flaps turns the model into a lawndart as its trimmed for much higher speed and without all that drag of the gear below the c/g. I need substantial amounts of up trim in the mix to offset this. 

 

In your case you do not have quite as much of a trim change as i dont think the model you have has flaps (??) but even so, you can set the mix up anyway. 

The way i recommend you do it is to assign a flap channel somewhere on the radio even if it does nothing. Mix the elevator to it (most tx's have a dedicated function for this already) and set a small amount on the rate to make sure its all working before going for a flight to set it up. 

 

When you go for a fly leave the menu open on the tx, and then slow the model down at altitude. IF you know your radio well you can beep the buttons yourself, if not employ someone to beep them for you. Keep adding more up elevator to the mix until the model stalls. When it does, put the flaps up to disconnect the mix. Then knock 5% or so off the mix and you are done. Now, with 'flaps' down the model is perfectly in trim for a speed/angle of attack just under stall and it will now be impossible to stall it on approach provided you leave the elevator alone. If the model is going long throttle back, if its short add power. You should not really need to touch the elevators during the whole final approach phase. 

 

Just be careful though, if you dont do a formalised approach with a dedicated downwind, base, final layout and just rock up on final still virtually flat out slamming the flaps down will simply case the model to do a backflip as it will be out of trim. As my glider instructor told me when flying full size, you did the landing about 3 minutes ago, but only now did you touch down. A fully thought out and planned landing circuit broken into chunks where do do things (throttle back, gear down,flaps half, rates high, flaps full...etc) in a checklist type fashion makes life a great deal easier and you can feed the flaps in slowly as the speed comes off. 

 

FInally, rates/expo and c/g. I have mentioned before that most models (warbirds especially) fly with excess rates on them. This makes them sensitive in the air so expo is added which gives an undesirable response when trying to land. This is a bit backwards as you need to tame the rates first, and then add expo if you need it. I hardly ever use it as its just not needed most of the time. However If the model is nose heavy, which is also very common, it will need a higher elevator rate to prevent a nose over and this contributes to the whole cycle of events. 

 

The long story short here is that the landing is done long before your wheels touch the runway. This can be a few minutes earlier at the start of the landing circuit (right height, speed etc) or it can be the week before back in the shed when you took some lead out and tweaked your setup. 

Edited October 11 by Jon H

[Simon Lumsdon 1]

Thanks Jon, really useful advice here, i really like idea of setting up ele trim into flap control (need to do this on extra which does have mixed flap/ailerons also) to slow things down.

 

think i now have a plan, fly some slow passes and feed in elevator to understand stall speed and then start to slow things down. I can do this on my fun fly’s so no reason why cant do it with mustang

 

its great to be able to get all this helpful advice, thanks to all

[Wihtgar]

I've been thinking of doing what Jon has suggested (no flap mix) using a Flight Mode on my Taranis Radio but not yet had the time to do it. Something to do in the dark winter evenings perhaps.

 

Nige

[GrumpyGnome]

I usually have three flight modes - take off, normal, landing

 

I'll have some mixes in the flight mode - bit of up for landing and reduced tickover, more up ele than down available for landing, possibly a tad more/less expo on some controls for takeoff and/or landing

 

I have mixing for undercarriage and flaps, separately, in case I want to use them in isolation, e.g. dirty pass, undercarriage check

[Martin Harris - Moderator]

9 hours ago, Simon Lumsdon 1 said:

think i now have a plan, fly some slow passes and feed in elevator to understand stall speed and then start to slow things down. I can do this on my fun fly’s so no reason why cant do it with mustang

Be prepared for a possible wing drop at the stall - most likely the left wing.  Unlike a funfly, some Mustangs can be quite vicious but should be easily recoverable at a decent height.  Use down elevator and rudder rather than aileron to pick up the wing...feed in the power relatively gently once recovery is initiated and don't yank the nose up - wait until decent flying speed has been attained.  It's a very good thing to practice and I would advise that you familiarise yourself with slow speed handling on any new model.

[Martin Harris - Moderator]

7 hours ago, GrumpyGnome said:

I usually have three flight modes - take off, normal, landing

 

I'll have some mixes in the flight mode - bit of up for landing and reduced tickover, more up ele than down available for landing, possibly a tad more/less expo on some controls for takeoff and/or landing

 

I have mixing for undercarriage and flaps, separately, in case I want to use them in isolation, e.g. dirty pass, undercarriage check

Some take the attitude that this sort of thing is "cheating" but re-trimming for different flight phases is standard practice on full size - but a lot easier with more time in the circuit and easier access to trimming controls.

[Jon H]

Flight modes are a variation on the same theme and I can see their utility in this case. I don't think my tx has that ability, but I have never checked for it. 

 

One word of warning if you use flaperons with this setup is to not use excessive aileron inputs. This flap mix idea puts the wing maybe at maybe 85 or 90% of its critical angle of attack, beyond which it will stall. If you lower an aileron, you increase the angle of attack on that wing and you may provoke a stall if you are this close to the critical aoa. It's for this reason I am not a fan of flaperons and have in the past cut a strip aileron into separate flap/aileron parts 

 

For your extra, if it's coming in like a rocket check the cg, it might be nose heavy. Most kits recommend a very conservative cg and significant amounts of weight can often be removed. I took over 1lb, or just under half of the total ballast out of my db hurricane and I can still stand to go a little more. Don't be scared. Unless it's miles out a tail heavy model is no bother to fly provided you don't also have massive rates. In fact a 'tail heavy' warbird is great as it won't spend it's life sniffing the dirt

[john stones 1 - Moderator]

Reading the first post, what comes to mind is have you got expo on the elevator ? Are you actually pulling to flare, but expo is hindering you (overdone the amount).

Moving the C.G is one of the most powerful means of setting a model up, far to many rigidly stick to "recommended" position coz that what the designer says, that's just your starting position. Final position should be where you have the model behaving as you want it to, only flying it will dictate that. Nitpick time, if it's flying well and as you want it to, the C.G is neither nose heavy nor tail heavy It's bang on.

 

[J D 8 - Moderator]

Very much agree with John above. I like to get scale/semiscale and trainer type power models to a set up that with full power they tend to climb, fly level at cruising and be in a steady decent with some power still on while on the way to a landing, no messing about with switching in/out this or that on the way to touchdown.  This is mostly achieved by getting CG and basic trim right. On some types thrust line may need adjustment.

  Some like heavy warbirds, precision aerobatic types, gliders, and things with odd thrust lines do have different needs though.

[Simon Lumsdon 1]

Well repaired the undercarriage today and went to the field and things were much better, bit more wind helped but landings much improved by slowing things down with a bit of elevator. Flies really well.

 

had some trouble with asp 91 fs and realised idle speed is too high (cuts out if throttle reduced past a point) and i need to fiddle with low speed needle. Also difficult to prime the engine once hot so need to get to the bottom of that

 

have also taken some lead out of nose that i dont think it needs,

 

very relieved after a few good landings, just need to fettle the engine now and get the idle speed down

[Jon H]

11 minutes ago, Simon Lumsdon 1 said:

cuts out if throttle reduced past a point

 

Straight cut means slow run too lean, stuttering stop too rich. Tweak 1/8 turn and go again. I would aim for 2000rpm on a 90 class 4 stroke as a top end for idle rpm. even 1800 should probably be ok. 

 

12 minutes ago, Simon Lumsdon 1 said:

Also difficult to prime the engine once hot

 

Dont bother, just crank it with the leccy starter and it will go. If not, this also points at a possible lean slow run.