Steve Hargreaves - Moderator Posted August 26, 2009 Share Posted August 26, 2009 A simple question, but then aren't they all if you know the answer..... My latest project (an IC model in fact) is going to have a 4 servo wing for no other real reason than because I can (have to justify all those mixers on my new FF10 after all!!!). This will allow me to split the ailerons & have full length ailerons for normal flight...link the inner section to the elevators as flaps & then use some crow braking to slow the model up for landing......should be interesting!!! My question is this......under crow braking is the outer section of the "ailerons" up or down? Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted August 26, 2009 Share Posted August 26, 2009 Hmmm, other more knowledgeable types will doubtless be along with the correct answrer, but if I recall correctly crow braking sees the ailerons go up as spoilerons, and the flaps down as errr ....flaps. Quote Link to comment Share on other sites More sharing options...
Slopetrashuk Posted August 26, 2009 Share Posted August 26, 2009 Hi Steve. CROW braking is flaps down ailerons up with some elevator compensations(usually down) to avoid a pitch change. In reality the flaps do most of the work and the ailerons are only raised slightly to de-camber the wing tips allowing you as pilot to increase the AoA of the wing without fear of a tipstall. This is different to up aileron 'Spoilerons' which basically do the same job but move further to dump lift as well as decamber the wing. Both operations require the pilot to fly the model on elevator. CROW is designed to create drag while retaining lift - the opposite of spoilerons. Which power model is it? You will rarely find that CROW brakes bring too much to the party on the power field. You might just find that the vertical descent will be greater than you desire as soon as those ailerons start to rise - unless of course your power model uses glider wing sections. Andy Quote Link to comment Share on other sites More sharing options...
Steve Hargreaves - Moderator Posted August 26, 2009 Author Share Posted August 26, 2009 Cheers Timbo/Andy.....thats what I thought... Andy..interesting point about the wing section.....the model is a collaborative design between a few club members. It is based on the WOT 4 but scaled up significantly & as you know the Wotty has a pretty thick wing section.....the prototype MK1 version came out very light & was pretty floaty hence my thinking to fit some for of airbrake.....maybe I shouldn't bother with crow braking on a model like this...? It would save me a couple of servos after all.... Quote Link to comment Share on other sites More sharing options...
Slopetrashuk Posted August 26, 2009 Share Posted August 26, 2009 A little flapperon slave coupled with elevator for the landing flare should be all that you'd need to slow it to a hover. Andy Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted August 26, 2009 Share Posted August 26, 2009 Steve, I have crow fitted on two gliders and it is a good help on the approach. I had a Glen's Maule and had separate servos on the flaps and ailerons, I never found a need for crow as flap was sufficient to slow it down for landing. What was good though was to have a setting (Flight Phase in Multiplex lingo) where the flaps were mixed to the ailerons to give greater aileron authority, i.e faster roll rate. You might want to try that. Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted August 26, 2009 Share Posted August 26, 2009 Steve, I have crow fitted on two gliders and it is a good help on the approach. I had a Glen's Maule and had separate servos on the flaps and ailerons, I never found a need for crow as flap was sufficient to slow it down for landing. What was good though was to have a setting (Flight Phase in Multiplex lingo) where the flaps were mixed to the ailerons to give greater aileron authority, i.e faster roll rate. You might want to try that. Quote Link to comment Share on other sites More sharing options...
Flash1 Posted September 24, 2010 Share Posted September 24, 2010 Can anyone tell me if it is possible to set up CROW on a Spectrum DX6i tx. And if so,how. Quote Link to comment Share on other sites More sharing options...
Ed Anderson Posted October 1, 2010 Share Posted October 1, 2010 I will be interested to hear how crow works for you on a power airplane. I have not heard of anyone using this configuration. For gliders, where we want to come in with more energy than we need to make the field Crow helps us dump that energy so we don't glide forever. But with a power plane where you can add and reduce power at will I don't see the value. But I don't fly power planes much so I will be interested to hear your report. Quote Link to comment Share on other sites More sharing options...
Ed Anderson Posted February 5, 2011 Share Posted February 5, 2011 Any updates? Quote Link to comment Share on other sites More sharing options...
Tom Wright 2 Posted February 5, 2011 Share Posted February 5, 2011 Most of us are in bed now ED.............zzzzzzzzzzzzzzzzzzzz Quote Link to comment Share on other sites More sharing options...
Phil 9 Posted February 5, 2011 Share Posted February 5, 2011 Quote Link to comment Share on other sites More sharing options...
Phil 9 Posted February 5, 2011 Share Posted February 5, 2011 Quad flaps are quite common http://www.youtube.com/watch?v=Q0YeqEOFS1Q full demo here Edited By Phil B on 05/02/2011 06:10:52 Quote Link to comment Share on other sites More sharing options...
Phil 9 Posted February 5, 2011 Share Posted February 5, 2011 Flash you can crow on a DX6i http://www.youtube.com/watch?v=HUfGmwT0620 but because you need 7 channels for quad flaps you can not get the flaps to follow the ailerons (So you dont get full quad flap function) use two aileron servos on aux and ail channels and use the flap function to use spiolerons. use a y lead for the two flap servos into the gear channel Quote Link to comment Share on other sites More sharing options...
Phil 9 Posted February 5, 2011 Share Posted February 5, 2011 Quote Link to comment Share on other sites More sharing options...
Geoff Smith 1 Posted February 5, 2011 Share Posted February 5, 2011 Forgive the ignorance gentlemen but what is crow a reference to please. Cheers Geoff Quote Link to comment Share on other sites More sharing options...
Hamish Posted February 5, 2011 Share Posted February 5, 2011 My understanding is to visualise a crow landing. Wings up(Ailerons) feet down (Flaps) Quote Link to comment Share on other sites More sharing options...
Tim Mackey Posted February 5, 2011 Share Posted February 5, 2011 Sometimes called butterfly too - I understand it to mean that it represents the rather complex shape that a crow ( or butterfly ) can form its wings into, as it approaches a landing. I think there are some slo-mo clips of it on the WWW somewhere. Quote Link to comment Share on other sites More sharing options...
Geoff Smith 1 Posted February 5, 2011 Share Posted February 5, 2011 Ah! sorted. thanks chaps. Geoff Quote Link to comment Share on other sites More sharing options...
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