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Old Nov 18, 2012, 08:06 PM
Hey Ya'll!! Watch THIS!!
Michael Paxton's Avatar
Nashville TN.
Joined Mar 2006
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Agreed. I think many people take this loss of control as radio failure. But in at least some cases, it's just loss of control because you're not flying you plane correctly!

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Originally Posted by Downwind3Zero View Post
Pilot error accounts for most losses. I have only lost one plane due to equipment malfunction but I have lost planes due to pilot error.
Any plane will tip stall if too slow or or wrong angle of attack - if you get into that situation however, it is still pilot error causing it.
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Old Nov 18, 2012, 08:33 PM
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Maybe I've missed something in reading about all the loses but in most cases it was said that they were close to or at full throttle so I'm not sure that "too slow" is the issue in most of these cases. The one thing I've read in a few posts is that you shouldn't "pull too hard in a turn". Some people have stated that they stay away from high rates on their throws to avoid the stalls. Any validity to these statements or observations? Comments from experienced 32 pilots? I appreciate any and all info as I will be building mine soon. Thanks.
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Old Nov 18, 2012, 08:47 PM
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United States, CO, Loveland
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We tend to think of stalling as a slow speed phenomina, but it's theoretically possible to stall an airfoil at any airspeed if you reach a critical angle of attack. In fact, high G loadings make this significantly worse. In full scale this is referred to as an accelerated stall.

Examined radio and power system. Only problem found (aside from the items broken in the crash) was a cold solder joint on the negative power lead to the ESC. Pretty scary - I'm going to check all my other EC5's. I'm assuming that pulled apart in the crash and was not related. When powered up with a seperate NIMH pack, the receiver, elevator servos and extensions appear work fine. I have not checked the flaps and ailerons yet but assuming they are fine.
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Old Nov 18, 2012, 08:48 PM
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United States, FL, Mt Dora
Joined Feb 2007
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i put 200-300 flights on my 32. hot tj80 3200 watts, I only fly high rates and have pulled severely hard G turns purposely trying to induce a stall, ... nothing ever happened. also did150mph snap rolls. never had an issue.

ive seen about a dozen 32's crash from pilot error. typical stalls in a slow turn at low altitude. seen to many fly it too slow as if it were a foamy.
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Old Nov 18, 2012, 08:51 PM
Never fly an A model anything!
jayb1rdz's Avatar
Antarctica
Joined Apr 2008
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My first 32 went in due to plain stupidity. I used old cells for the maiden and it hit "hard LVC" when it was too low and banked too steep for recover without power.....see stupid.

There is very a strong correlation between experience and model survival. I learned another lesson after owning many EDFs. If you build stock, and have commensurate experience, you'll have no issues. If you hop it up, do it knowing that changes to wing loading will have consequences to:-
. take-off and landing speeds and distance
. stall speeds
. gear strength.
. amp draw, motor temp, esc temp etc etc.

In short, the manufacturer has not done all the work to cover all the possible variations and you are on your own.....except for the advice here at RCG.
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Old Nov 18, 2012, 09:30 PM
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well I have flown probably more than 15 diff Habu32's and have hundreds of flights on them never once did I experience a tip stall that I wasnt expecting......in other words on flare just before touchdown and even that was very rare. I think the main cause of some of the issues is improper setup of the model, mainly cg (too nose heavy), elevator throw (too much) and then pilot error. weight plays a roll but most guys build this within 7-8lbs and that is fine so this is probably not the problem. I see it as a too much elev throw issue and it goes like this.....stock cg is a little nose heavy and thus more elev throw is required. the stock 6s setup per the manual works pretty good, but if you move the cg back for better performance then you also need to reduce your elev throws and this is where the problem happens I think most do nothing and just fly, some will add expo to soften the stick but this creates a knee that if in flight you pull too much elev it will snap at any speed. I think this accounts for the high speed snap or tip stall issues most are seeing, for the true tip stall on landing approach this is just a matter of the pilot getting the model too slow or too high aoa or both. setup of the models trim when dirty is the key or the problem. when setup correctly with gear and flaps deployed the model should be trimed for a slight decent angle so that the pilot is required to hold a little elev to fly level, the entire landing sequence should be in a slight decent the whole way thru with the nose down all the way to the runway then bring up the nose and ride the flare to touch down.
getting the cg and max throw of the elev right is critical to minimizing these issues. one more thing adding crow also helps with tip stall by mechanically adding washout to the wing. this lowers the airspeed at which the wingtip stops flying (tipstall) so very beneficial
so this is my take on why some tipstall and some dont
this model is very popular and very proven so for this one to me it comes down to setup of the model and in particular the cg and max elev throw.
John
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Old Nov 18, 2012, 09:50 PM
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Wow...very good info. Thanks to all who have given their input/insight. It all makes a lot of sense and has cleared up quite a few questions/concerns that I have. From everyones experience, what's a good cg? My power set up will be a TJ80 1509 2Y. Again, thanks to all.

jcdfrd, glad you mentioned crow cause I was actually contemplating setting it up on the 32 and you've just confirmed for me that it's a good idea.
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Old Nov 18, 2012, 09:51 PM
Proud RC Addict
United States, UT, American Fork
Joined Nov 2009
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I guess I could add my opinion... having just lost mine. It flew wonderfully. Took just a few clicks to right trim to get it to track great and then I flew around for a while getting used to it before attempting a few low passes with flaps to see how it would handle for landing. Just my own error for ignoring the light poles! I thought for sure it wasn't anywhere near them. Oops. So +1 to pilot error.
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Old Nov 18, 2012, 10:00 PM
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Quote:
Originally Posted by mulicheng View Post
I guess I could add my opinion... having just lost mine. It flew wonderfully. Took just a few clicks to right trim to get it to track great and then I flew around for a while getting used to it before attempting a few low passes with flaps to see how it would handle for landing. Just my own error for ignoring the light poles! I thought for sure it wasn't anywhere near them. Oops. So +1 to pilot error.
lol!!!!
ya I try not to fly around trees or poles they always reach out and grab me
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Old Nov 18, 2012, 10:00 PM
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United States, CO, Loveland
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First of all - no matter what, this was pilot error. Even if there was an equipment or set up problem, that's me, too. I just want to learn from the experience, and that means understanding it.

Cg was right at the aft limit (subject to some variation on how closely I placed the battery to the mark), low rate throws reduced about 10% to reduce sensitivity, 35% expo. jcdfrd is correct that expo can make it worse - the response is non-linear and significantly sharper if you get past the knee. But I seriously doubt I was doing this. I think the best scenario so far is the rear Cg and I pulled it a bit too tight. Definately wasn't going slow.
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Old Nov 18, 2012, 10:08 PM
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Quote:
Originally Posted by DamonH View Post
Wow...very good info. Thanks to all who have given their input/insight. It all makes a lot of sense and has cleared up quite a few questions/concerns that I have. From everyones experience, what's a good cg? My power set up will be a TJ80 1509 2Y. Again, thanks to all.

jcdfrd, glad you mentioned crow cause I was actually contemplating setting it up on the 32 and you've just confirmed for me that it's a good idea.
no problem DamonH
if your new to crow then go slow with it. you only need like 1mm to gain the mechanical washout effect after that it becomes a good braking function for fast sport jets I would recommend 1-2mm to start with and then increase 1mm at time to find your sweet spot, on our 12s Bu32 we used 5mm crow for full flap and it slows down fast so it is something you have to get used to.
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Old Nov 18, 2012, 10:11 PM
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United States, NM, Clovis
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Quote:
Originally Posted by jcdfrd View Post
no problem DamonH
if your new to crow then go slow with it. you only need like 1mm to gain the mechanical washout effect after that it becomes a good braking function for fast sport jets I would recommend 1-2mm to start with and then increase 1mm at time to find your sweet spot, on our 12s Bu32 we used 5mm crow for full flap and it slows down fast so it is something you have to get used to.
Sounds good...I am new to crow so I will definately heed your advice and start slow.
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Old Nov 18, 2012, 10:31 PM
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Tam showed me this trick a long time ago when we started racing Bu32's
for cg, install the battery and canopy and get ready to fly, set the model on its gear on the table or on the ground. push the tail down to the ground and let go, for us the cg is perfect when the tail just almost wants to stay on the ground but slowly rotates back to the nose wheel......this is a fast and easy way to check cg before every flight
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Old Nov 18, 2012, 10:39 PM
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United States, NM, Clovis
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Quote:
Originally Posted by jcdfrd View Post
Tam showed me this trick a long time ago when we started racing Bu32's
for cg, install the battery and canopy and get ready to fly, set the model on its gear on the table or on the ground. push the tail down to the ground and let go, for us the cg is perfect when the tail just almost wants to stay on the ground but slowly rotates back to the nose wheel......this is a fast and easy way to check cg before every flight
Nice! I've gotta give that a try. Thanks.
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Old Nov 18, 2012, 10:43 PM
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United States, MO, Warrensburg
Joined Feb 2008
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Quote:
Originally Posted by jcdfrd View Post
Tam showed me this trick a long time ago when we started racing Bu32's
for cg, install the battery and canopy and get ready to fly, set the model on its gear on the table or on the ground. push the tail down to the ground and let go, for us the cg is perfect when the tail just almost wants to stay on the ground but slowly rotates back to the nose wheel......this is a fast and easy way to check cg before every flight
Yes, it works nicely!
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