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Old Feb 22, 2012, 01:00 AM
6 months to finish a rtf
pulsery2k1's Avatar
upstate ny
Joined Jun 2003
1,859 Posts
Doug W

this is model aviation , you buy and you fly you don't really
have to understand how an aircraft fly's .
so its easy to get a lot of mis infomation

it started with the model in the crash , its simple the model got
to slow - would flaps have helped -- maybe - but it was the
steep turn - that did the model in . if you fly you know you don't
make steep turn low and slow - also alot of model pilots fly
only using ailerons - no rudder .
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Old Feb 22, 2012, 04:41 AM
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NickM91's Avatar
Australia, WA, Perth
Joined Jan 2009
250 Posts
Quote:
Originally Posted by Doug W View Post
Where on earth is your data coming from on stalls with flaps vs.without in the sense of dropping a wing? Flaps by design create higher lift and a lower stall speed. Go rent a standard flight school 172, add full flaps, pull the power back, and stall it- gentle as a kitten. Take the same 172, no flaps, full power departure stall and you'll get a cute little torque roll (I mean, it's not a Pitts Special or anything) at the top of the stall- all P-factor and torque.

Stall tendencies (the variables you allude to) are functions of wing loading, angle of attack, bank angle (that will drop a wing on you) coordinated/un-coordinated flight, power settings, CG (yes) and yes, flaps.

But in that equation, flaps will generally provide a more gentle, as opposed to less gentle stall. It seems you're singling out flaps- what did they ever do to harm anybody?

Poor little flaps You probably hurt their feelings.

(and I am of course, just kidding around with you)
Haha no worries.

Okay maybe a bit unfair as yes, there are many many more factors at play, not referencing to the crash in the video, just a generic stall/wing drop scenario.

Though the stall speed is reduce as the Cl is increased, the actual stall angle is decreased (slats and other BLC devices will raise it). In an aircraft where the stall originates at the root, in the event of a wing drop at the stall (due to imbalance, roll etc etc) there will be a more severe drop with flaps extended than with them retracted as a higher proportion of the wings lift will be lost on that side, if you follow me.

The theory I have studied suggest that anyway and it seems well backed up by my experiences in the real thing.

To keep things simple differential lift will cause a wing drop whether its tip stall or sorcery at work


Flaps aren't all good, they reduce lateral stability

Either way it was a good crash
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Old Feb 22, 2012, 07:57 AM
ich bauen groß modell flugzeug
Keenan smith's Avatar
United Kingdom, London
Joined Dec 2010
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^^ what he said!!
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Old Feb 22, 2012, 12:37 PM
WIFE HAND LAUNCHED MY PLANES!
Spyro37's Avatar
Joined Jun 2009
2,241 Posts
Quote:
Originally Posted by k.smith459 View Post
your gonna need an inbd flap other wise shes gonna be a stallin Devil!
Since when did flaps prevent stalls avoiding crash on RC flying?
In fact, experienced modelers/ builders would sometime add a small degree of aileron "wash-outs" to reduce chances of stall.

But most importantly, a warning and quote from Bamaguy (post #3110):
Be careful on that "loop around for landing"! You may really excite the crowd by auguring that baby in. If you're low, slow and dirty and turn too tight it WILL stop flying

Unfortunately, there are limits to flying RC planes that needs to be observed in my opinion, otherwise, could result to disaster. & Just as Scott said, the pilot is used to fly a 3pound plane this size.

The use of right amount of throttle & speed should be the recommendation to avoid this unfortunate crash. Flaps is not a "solution" to this crash.
Try to build an 8 pound 737, deploy the flaps, fly it this slow, and let us know
Just an opinion as an RC flyer, & not a full scale.
- Spyro
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Old Feb 22, 2012, 12:51 PM
ich bauen groß modell flugzeug
Keenan smith's Avatar
United Kingdom, London
Joined Dec 2010
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Edit i meant tip stallin when at lower speeds !
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Old Feb 22, 2012, 02:22 PM
6 months to finish a rtf
pulsery2k1's Avatar
upstate ny
Joined Jun 2003
1,859 Posts
there is a very big difference from flying a real aircraft and a model
aircraft . the model is much harder to fly why ? Because in the real
aircraft your in it ,you have instruments ,. airspeed Info. you have
had training and have been checked out to fly that aircraft.
the real aircraft has been built test flown and has FAA certification.

the model is built by the pilot and setup by the pilot -in my experience
as a club instructor most don't use the control throws given in the
manual .they tend to put to much throw in if you have been flying
3D setting up your 737 with the same throws won't be good.
the air speed is visual and unless you take the time to
do some stall's and slow flight high up , the first stall will most likly
be low and fatal as in video- in a real aircraft there are other clues
stall warning horn's stick shaker , audio warnings .
with a model all warnings are visual in video you can see the model
getting slow and approching a stall .
a lot of modeler's fly with only Ailerons ,when an aircraft is slow
it needs to make shallow coordinated turns
for this I use the ail/rudder mix on my tranmitter I turn it on
for take off and landing. you also need to keep your speed up
till on final , if your model is properly set up ,and you don't make
steep turn when the model is slow , you should have no problems
so it not the flaps it more your seyup and flying style.
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Old Feb 22, 2012, 03:01 PM
Don't Move I've Dropped My Nut
bamaguy's Avatar
United States, AL, Huntsville
Joined Feb 2009
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Big plus 1. Pulsery2k1!!

-Gary
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Old Feb 22, 2012, 04:42 PM
WIFE HAND LAUNCHED MY PLANES!
Spyro37's Avatar
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2,241 Posts
Well said Pulsery2k1.
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Old Feb 22, 2012, 06:13 PM
TAFTS
Chandler, AZ
Joined Apr 2008
334 Posts
Good Job on the explanations Spyro and Pulsery.

Mike is an excellent pilot. You can watch lots of him flying airliners at neffwaffe on Youtube. He really does build airliners this size that weigh 3 pounds. They are constructed of depron from blown-up card models. His 737 is almost exactly the same size and really does weigh 3 pounds. He flies it on one 2200 3S pack. He totally manned up and said it was coming in much faster than he was used to and just got behind it. The less than perfect (read between the lines) linkages and set up aggravated the situation. Not his words, mine. He accepted all the blame.


After the re-build and re-rigging, this airplane now has a predictable stall without any tendency to drop a tip if somewhat coordinated. The best, and most frequent advice I give intermediate pilots is to teach their left thumb (mode 2) to contribute to the flight. Its not just for taxing out....



Scott
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Old Feb 22, 2012, 07:50 PM
6 months to finish a rtf
pulsery2k1's Avatar
upstate ny
Joined Jun 2003
1,859 Posts
Scott Todd

yes I have seen neffwaffe model's and him flying them on youtube
excellent work , but his model as you say are 3 lbs for the same
sized model , you can see the diffrence of how his fly in his video's.
I belive he is also airline pilot too .
so its easy to understand now flying a model the same size ,but twice
the weight could be a little harder .
modeling is about having fun , I also tend not to give advice or sound
like a know it all - but as an instructor on real and model aircraft
it comes down to learning to fly correctly and avoid accidents.
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Old Feb 23, 2012, 06:30 PM
Registered User
Joined May 2011
31 Posts
not to get off subject guys my f-16 is stuck in a tree and i cant get it down
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Old Feb 23, 2012, 06:39 PM
ich bauen groß modell flugzeug
Keenan smith's Avatar
United Kingdom, London
Joined Dec 2010
6,838 Posts
(hillbilly joke! ) how do you get a plane outta a tree

A shotguun!
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Old Feb 23, 2012, 11:12 PM
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Doug W's Avatar
United States, WA, Seattle
Joined Jul 2010
481 Posts
Quote:
Originally Posted by pulsery2k1 View Post
Doug W

this is model aviation , you buy and you fly you don't really
have to understand how an aircraft fly's .
so its easy to get a lot of mis infomation

it started with the model in the crash , its simple the model got
to slow - would flaps have helped -- maybe - but it was the
steep turn - that did the model in . if you fly you know you don't
make steep turn low and slow - also alot of model pilots fly
only using ailerons - no rudder .
Totally agree and well said Pulsery That said, I still think to some degree, there are several areas where full size aviation is very helpful and certain aspects could be adopted for model aviation that would prevent a number of preventable and costly accidents (thereby of course, also saving the lives of untold numbers of innocent, imaginary souls)
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Old Feb 24, 2012, 11:10 AM
Registered User
Bermuda, Pembroke, Hamilton
Joined Aug 2010
12 Posts
I hav'nt bought mine yet but can't stop thinking about the livery decals.
Some ideas (or the good old Qantas).
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Old Feb 24, 2012, 11:19 AM
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Bermuda, Pembroke, Hamilton
Joined Aug 2010
12 Posts
Bermuda

Or this one I designed for a Bermuda based private jet company.
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