|dave windymiller||25/12/2018 20:02:25|
75 forum posts
My Mosie had a habit of tip stalling. I now have reflex ie up aileron on both wings and reduced down throw on ailerons. It is far less prone to dropping a wing now.
The last few times of flying its behaved like it had a rearward c of g with a lot of pitch sensitivity. Ive added some 200g of lead to the nose and have minimum throws on elevator and 40% expo but still its a roller coaster ride.
Can upward reflex in the ailerons cause or increase this effect of pitch instability?
Edited By dave windymiller on 25/12/2018 20:03:39
8531 forum posts
Check to see if the wings have equal wash out in each wing....or wash in. Washout is your friend. It makes the inner part of the wing stall first, leaving the tips still flying.
|Denis Watkins||25/12/2018 20:16:06|
|3746 forum posts|
Zero expo on elevators Dave
And reduce the throw, with a slightly higher throw on the rate switch
404 forum posts
Is this the Seagull one, some people have been using a CoG of 130mm back from the leading edge not the 150mm in the manual to reduce the pitch sensitivity. I have a Brain Taylor one, and the CoG on that is further forward than the seagull one, 140mm from the front of the upper radiator inlet and my BT flies really well without being pitch sensitive. Mine balanced slightly nose down at 140mm with empty fuel tanks and retracts up, so the actual CoG was slightly less than 140mm. Some BT Mossie's have flown with the CoG around 125mm or so and these have also flown well. The BT model has some wash out built in and I have not needed reflex.
Edited By PeterF on 25/12/2018 22:24:08
|Chris Walby||25/12/2018 22:23:23|
944 forum posts
DaveW, Sorry I am no expert, but I think adding reflex is not a simple solution as it has multiple effects depending on Aileen size/position.
What model is it and what are the various setting, my Seagull Mosquito has lower elevator, but higher aileron throws + C of G is further forward than Seagull state
P.S. if you are reducing outer wing lift should the tip stall be worse?
1900 forum posts
There is little loss of lift with reflex/washout this is replaced as the AOA of the wing increases thereby keeping the tip out of the stalled condition I think???
|Tom Sharp 2||26/12/2018 02:36:30|
3432 forum posts
CofG moves when the wheels are retracted.
|Jon - Laser Engines||26/12/2018 08:47:03|
|4730 forum posts|
It sounds like its being a warbird to me. Reduce the elevator rate until its nice to fly, and as already suggested i recommend you loose the expo until the rates are right.
I recently had experience with a seagull hurricane and we ended up using half the low rate recommended in the kit.
Its also possible your landing technique is leading you do the tip stall situation you mention. If you do a relatively long and flat approach holding the nose up with elevator and power then a tip stall is very likely, if however you do a steep approach with lots of flap (ie, drag) and virtually no elevator the wing is not going to stall on you until you as you come in. Just remember to add power as you pull into the flare and dont try to 3 point it. Land on the mains and let it roll out with the tail in the air.
|Trevor Crook||26/12/2018 10:58:37|
|826 forum posts|
Wise words Jon. I have a Black Horse Mossie which flies very well and has never bitten me, using your landing technique, which I use for all my warbirds.
When I get a chance I'll see where the c of g is as a percentage of chord, and report back.
|Danny Fenton||26/12/2018 16:13:49|
9082 forum posts
I have flown the Seagull Mossie at 150 and was very lucky to get it down in one piece. with the C of G forward an inch it was much better. Like others have said adding reflex increases the wing loading as it reduces lift. So swings and round abouts. Mine flies fine at around 125mm and slows down well without stalling.
The C og G does move when the wheels are retracted, but the wheels provided by Seagull are very light, and I found it moved very little when up, but measure the c of g with them up, just to be safe. I know some have changed the wheels to heavy items, this may then be more of an issue. but either way measure with wheels up.
Good luck and have fun.....
|dave windymiller||31/12/2018 16:36:50|
75 forum posts
Ive reduced throws and managed to shed a few grams from the rear and will decrease the reflex on the ailerons and try again tomorrow.
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