Acrowot - Landings

[Paul Adams]

What is the best way to land an Acrowot so it does not bounce. At first I thought it was just me, but after trying a number of methods ranging from flying it down to the ground, floating in, balancing throttle with elevator to do a three point landing all I get is a bounce. I do not know if its just my model but looking on youtube it appears to be a common feature of Acrowot landings.

I am open to ideas

 

Edited By Paul Adams on 03/12/2011 15:39:19

[Biggles' Elder Brother - Moderator]

I wasn't aware that the Acrowot was any more "bounce prone" than most models

 

Whether you get a bounce or not will depend on;

 

1. How "springy" the U/C is - I don't think the Acrowot has a particularly springy under cart.

 

2. How hard the ground is - you're more likely to get a bounce when the ground is very hard - e.g. in a long dry hot summer (we wish!) or prolonged frost (more like it!)

 

3. Your vertical speed at touch down. If its high you will bounce!

 

Well there isn't much we can do about 1 and 2 so let's look at 3. Controlling your vertical speed at touch down is all in the flair. You need to "hold the model off" in the very final stages so she just sinks slowly onto the ground. The Acrowot being a low winger will have a pronounced "ground effect" in the last foot to eighteen inches - this should help you to cushion the touch down. The only thing to be careful of is not to over do it in the flair or you'll stall it in obviously. But its usually pretty obvious when you are in that territory as the controls go very mushy beforehand usually.

 

I can only suggest loads of practice "touch and goes" paying particular attention to timing the flair correctly

 

BEB

[Former Member]

[This posting has been removed]

[Paul Adams]

Hi Biggles - Thanks for the advise, Its strange, all the other models I fly no problem (Pattern ships to 3d) its just this one model which refuses to land without bouncing.

 

Thanks Tom, Will go it a go tomorrow and see if it helps

[Steve W-O]

Another cause could be that as you touch down, the tail drops (CoG behind the wheels) and increases the angle of attack, so it bounces.

 

Maybe try a higher angle of attack, more throttle to keep it up at the low speed, and lose the throttle as it touches down, hopefully it will be stalled as it touches down.

 

But not is a good breeze, you need a bit more speed then.

 

Had a similar problem with floating, and had to practice and practice coming in slower with more throttle and a nose up attitude.

[fly boy3]

What size engine is on the model Paul. I noticed that when there was a glut of Acrowots on our patch The models with the 90+ engines installed always had more problems bringing them in, (probably due to extra weight) than the lower powered ones. Best combination seen flying was Acrowot with 53 irvine. Also the bigger engined ones lost their u/c far more than average LoL. Personaly I always had a problem landing mine. Too fast it bounced, too slow model damage. Otherwise it is a classic model. Cheers

Edited By fly boy3 on 03/12/2011 22:13:33

[Glyn R]

I have flown both Glow (Irvine 53) and Electric (Turnigy 4250 1150watt). The only way is to fly in with a long touch down. Both my Acrowots had the GF undercart which can delaminate and become springy.

[Paul Adams]

I have solved it.

 

Basically light winds today so was able to re-trim the model. Engine down thrust increased by 1 washer behind the top engine mounts, C of G moved back in stages until just needed a touch of down to fly inverted (I think I taped 10 pennies and a washer to the tail plane). The model now flies a lot better. What I was not expecting however was the transformation it made to the landings. It now slows down much easier and can be brought in quite slowly for perfect two or three point landings. No more bounce and improved flying, Brilliant.

 

In answer to fly boy 3 - Engine fitted OS 91 Four stroke, 13 x 8 prop - Gives brilliant power to weight ratio with a nice four stroke engine sound.

[Paul Adams]

Another change I made during the week which I had forgotten about was that I changed the fuel tank as it was leaking. Originally it was a 12oz tank and at the end of a flight it still was 1/2 full, so I reduced the size to 8 oz. Therefore for the same length flight (timer set to 10 min) I would be landing with 4 oz less fuel in the tank which would not only decrease the model weight but also would move the C of G further back from last weeks flying position.

[fly boy3]

Congrats. Paul. There is nothing to beat a good landing at the end of the day. Cheers  I also agree with Glyn R,  a long fly in with power.

Edited By fly boy3 on 10/12/2011 19:04:22

Edited By fly boy3 on 10/12/2011 19:05:31

[ken anderson.]

must admit---i've read this post a few times over the past week......the A/wot i own c/w a 91 4st in it is no problem to land at all......most of chriss foss model(Wots) are 'floaters'....the only thing with the 91 4st is your.... at the top end of the weight for the model...but still no probs landing......

 

 

ken anderson ne..1.......91..4st...A/Wot dept.....