The Fokker ends up on its nose
|Kev Bamber||07/03/2011 17:45:54|
42 forum posts
I have a Flair Baronette Triplane which flies well, no problem with taking off, but I really struggle with landing.
I can place her down straight into wind tracking dead straight, but the moment the tail drops, more often than not, she will turn onto one wheel, dig a lower wing tip in, and go over on her nose breaking yet another set of top wing struts.
I've put axe handle guides on the lower wing tips to reduce digging in, nipped a bit of toe-in on the wheels & increased prop size to improve air flow over the tail, but still, round and over she goes.
Sometimes, just sometimes, I will land her fine, but can't work out what i'm doing right when I land well, and what i'm doing wrong when she ground loops & ends up on her nose.
I recognise this is a quirk of DR1's but any advice to improve my landing success rate would be much appreciated.
A typical landing pic is shown below.
Edited By Kev Bamber on 07/03/2011 17:49:19
|Alan Cantwell||07/03/2011 18:10:06|
|3039 forum posts|
my quarter scale one spent more time on its back than on its wheels, finally found the best way is to bring it in on its mains, with power on, decrease the power, let the tail sit down, and have LOTS of up elevaotr on a switch, trouble is, the back end is blanketted by the mid wing, they are great fun to fly, but i would fit a BIG tank, at least you will get one long decent flight
1422 forum posts
I have seen the full sized replica landing at Breghton. It too, has been known to ground loop.
|richard cohen||07/03/2011 20:15:23|
289 forum posts
Kev, I remember seeing a model fitted with a thin piano wire outrigger on each wing tip angled back to trail slightly. It was barely visable in the air but had enough spring to keep the wings from dropping but not so stiff as to put undue load on the wing. Model might rock side to side but shouldn't dig in, all you need to do is keep the tail down.
Depends on your balance of scale looks versus practical flying.
I am thinking of fitting a thin wire hoop (like the Avro 504) to the wing tips of my SE5a to stop tarmac rash from our runway. Might not be a scale addition but will prevent covering damage when i have an iffy landing. (or else i need to find a grass strip )
|Allan Bennett||07/03/2011 20:42:28|
|1775 forum posts|
|I can't really add to what the others have said, except that on those rare occasions that you manage a landing without tipping up, it may be because you're landing exactly into wind. I imagine it needs just the slightest hint of a cross wind to start the chain of events that results in one wing digging in.|
|Gary Binnie||07/03/2011 20:43:11|
534 forum posts
I'm building a Baronette (very slowly!).
I think there is a note in the instructions to fix both wheels to the axle (so that they rotate together) to improve this.
It's worth a try. Is it any worse or better trying a three-point landing?
1703 forum posts
|The Fokker Triplane is notorious for poor ground handling !|
|stu knowles||07/03/2011 20:54:50|
|616 forum posts|
I seem to remember that mine performed better if the moment the mainwheels touched the ground, I released the elevator and let it slow down with the tail high. After it has slowed a little, then pull the tail down with up elevator. Sounds counter intuitive but it worked.
Still had to be smack into wind though.
|Biggles' Elder Brother - Moderator||07/03/2011 21:13:58|
15748 forum posts
Fixing both wheels to a single axle so that they rotate together or not at all is worth trying. But as the others have said there really is a limit to what you can do about this. Smack into wind, power on, mains touching first, wings dead level - the only way its going to work - good luck!
PS At least you strip is like a bowling green by the looks of things - ours is like a ploughed field bt comparison!
|Alan Cantwell||07/03/2011 21:18:15|
|3039 forum posts|
i really fancied, with mine, haveing a HUGE indecent amount of up elevator on the rate switch, linked to expo, get it down, pull the elevator UP, now try going over you, erm, nice triplane
|Biggles' Elder Brother - Moderator||07/03/2011 21:21:53|
15748 forum posts
I actually do that on my chippie! I have a special high rate elevator setting just for taxing out, take off and landing run out! Plenty of expo on it no problem! Looks an Extra 3D with a "barn door" elevator sticking up when taxing! But its backside stays on the grass - just!
651 forum posts
Make sure that any weighty items (like the battery or church roof in the nose) are as low as possible to keep the CoG low.
My Baronette has the wheels further forward to avoid tipping, but this makes it very prone to ground looping. I've moved them back by about half an inch and will move them back again when I've repaired it from a serious ground loop incident, hoping to find an optimum position
I find the ground looping very frustrating, the blanketing of the rudder is One second the rudder doesn't react then the next you've full opposite rudder to hold it straight, until suddenly the rudder reacts violently and you've ground looped. Once in the air it is great fun, with rudder turns in it's own length, pretty much as the original, and cross control turns using rudder to turn and opposite aileron to hold the wing up. It's quite unlike anything else I've flown, which is why I'm taking the trouble to repair the broken spars and re-cover etc etc....... Let us know how you get on.
|stu knowles||08/03/2011 06:31:27|
|616 forum posts|
Thats funny, mine is laid up with broken spars too! The fully sheeted centre section / sudden change to open outer wing section is an abrupt change in strength / flexibility, probably not a good design point. Trouble is that if one spar breaks, chances are that all three break.
One day I would like to try the larger version. Does it handle any better??
|David Davis||08/03/2011 07:33:00|
3851 forum posts
Mine awaits repairs too. Nasty little brute always ground looping. The only time it flew was when the club expert managed to get it airbourne. I let him land it too! In flight it was good fun and very atmospheric, being finished in the colours of Hans Weiss, one of Richtofen's flight leaders. The club expert said that the bigger ones were easier to fly.
Mine is fitted with an OS40FS. I plan to replace it with a Thunder Tigre 54 to see whether it will cure the ground looping problems by not staying on the ground long enough!
On the other hand if someone wants to make me an offer for it.....
|Danny Fenton||08/03/2011 09:45:31|
9787 forum posts
Mine is electric, with a fairly big prop, and though I haven't flown it much, it seems quite happy as long as you land with some power/propwash to keep the surfaces working. a headwind is helpful too, but of course you must land straight into the wind!
Even then the slightest undulation and its off lol
|Bob Cotsford||08/03/2011 09:55:21|
8844 forum posts
Mines got a gyro on the rudder, it doesn't suffer from groundlooping but it still flips on landing. I wonder if Danny's lack of problems has anything to do with the superb Greenacres grass? I tend to fly from a farmers field for the most part and long grass definitely doesn't help.
As for broken wings, 4 of the panels have repairs to the trailing edges as results of landing flips.
I've also Dannified it with leccy motor and 8 LiFe cells (4*2). Power is not an issue
|Danny Fenton||08/03/2011 10:04:28|
9787 forum posts
Yes thats a very fair point I do have that lovely grass LOL
Glad you are still enjoying yours Bob Did you put your LiFe cells low down in the fus as I have?
|Bob Cotsford||08/03/2011 12:47:42|
8844 forum posts
Hi Danny. Yes, the cells are in the bottom of the nose resting on the UC mounting and right back against the lower wing LE. The leads exit handily under the motor mount so i can both connect up and charge without taking any wings off.
I've turned into a fair weather flier this year so it's been laid up since last year, but when it warms up enough to mow a strip I need to play with the CofG a little. It may be a little more nose heavy than need be, which won't help the tripping up situation.
|Tom Wright 2||08/03/2011 13:34:53|
3908 forum posts
Hi Danny Approach and touch down dead into wind goes with out saying ,i use power to check the sink through the round out ,and touch down still using power to keep sink and ground speed low ,this works every time for my DR1 , the wing loading is about 14 oz/sq ft ,i think as the wing loading goes up the problem is more pronounced.
|Mike L||08/03/2011 14:38:19|
54 forum posts
This is the maiden landing of my Gloster Gamecock, fast (too fast probably), lots of up elevator on touch down. Later discovered veering to right was sticky wheel.
I get about 50:50 success rate with landing and it not nosing over, which is very frustrating. I know elevator is certainly a key factor but can't decide if approach should be slow or fast. DIrect into the wind is equally important as well.
I have a Gladiator and the plan emphasised a low flat approach, I dont think it made much difference and still had the desire to nose over. Won't post that one, cos includes bad language at nosing over point.
Although we have a "flat" site area its pretty rutted which doesn't help.
Edited By Mike L on 08/03/2011 14:41:50
Edited By Mike L on 08/03/2011 14:47:43
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