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To Gyro or not to Gyro?

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Old 11-18-2008, 06:15 AM
  #76
tahustvedt
 
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Default RE: To Gyro or not to Gyro?

Hi.

It doesn't feel nose heavy in flight other than the rotation is a bit quick. I think that it would be able to rotate and take off much earlier if it had a more rearward CG. I have balanced it at 133 mm / 5-1/4" according to the recommendation from the manufacturer (Tamjet). I will try experimenting with moving the CG back a little.


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ORIGINAL: Craig B.

Hi tahustvedt,

Sounds to me like you have a nose heavy aircraft. My 2 1/8 F16 rotate that smothly you would probably be unable to pick the point at which the model left the ground, but my c of g (skymaster F16's) is at 175mm ("recommended" is around 140!) My model flies beautifully right way up and inverted, rotates and lands well. Where is your c of g and how are you measuring it? Mine has been measured accurate to a mm using a suspension jig. The gyro won't be able to compensate for what may be a fundamental problem with the setup.

As an aside, a fellow very experienced jet modeller just did some calculations using a aerofoil program on the correct c of g for our F16's.....guess what the majic number was? 176mm! 140mm puts the c of g on the leading edge at the MAC, ludicrous! Gyro won't fix that, especially in rate mode.

Hope that helps,

Hi David, thanks for your input.

Regards,

Craig.
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Old 11-18-2008, 06:00 PM
  #77
Doug Cronkhite
 
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Default RE: To Gyro or not to Gyro?

Check to be sure your aircraft isn´t sitting at negative incidence either. That will cause the nose to "pop" up as you rotate as well. 0 or even +1 degree is best.
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Old 11-19-2008, 03:42 AM
  #78
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Default RE: To Gyro or not to Gyro?

Hi,

one question:

When you use a gyro on nose gear (for take off and landing) you use Heading lock mode or normal mode?

For take off no problem i think in HH, but for landing... during flight, gyros is desactivate and you don't know the direction lock by the gyro during retract and activation for landing...

I have kust tested normal model on my F15 skymaster nose (gyro ASSAN G410, cheap and well)

Regards,

Sébastien
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Old 11-19-2008, 04:27 PM
  #79
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Default RE: To Gyro or not to Gyro?


Quote:
ORIGINAL: autorot

Hi,

one question:

When you use a gyro on nose gear (for take off and landing) you use Heading lock mode or normal mode?

For take off no problem i think in HH, but for landing... during flight, gyros is desactivate and you don't know the direction lock by the gyro during retract and activation for landing...

I have kust tested normal model on my F15 skymaster nose (gyro ASSAN G410, cheap and well)

Regards,

Sébastien
You can switch on/off HH mode anytime during flight, as long as you don't change sub-trims, and sticks are centered when you do so. I use 3 Futaba 401's in 3D airplane, and I switch from HH, to non-HH, and OFF throughout the flight. I might swich on/off 10 times in 15 minute flight. Again, don't change sub-trims, and leave sticks centered when you switch on gyros.
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Old 11-20-2008, 12:56 AM
  #80
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Default RE: To Gyro or not to Gyro?

yes with gyro on elevator or rudder or aileron, but with the gear nose i think it's different.
for example: If i switch in HH mode or activate gyro before landing , the gyro lock a cap but the plane will change is direction (last virage/ correction..etc) so when the nose gear touch the runway, the wheel will not be centered!
Another example:
With HH during take off, no problem. i retract the gear with gyro activate and for landing same problem, i don't know what cap keeps the gyro! so the nose will be not centered for landing...
you unterstand my example?

Regards,

Sébastien
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Old 11-20-2008, 02:08 AM
  #81
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Default RE: To Gyro or not to Gyro?

Raf,
The JR G410T Tail Lock Gyro is no longer availble. What JR Gyro out now do you think best replaces it.

Thanks,

Wayne

This description of the 410 describes what I am looking for the nose wheel.

JR G410T Tail Lock Gyro:
Great for beginners and intermediate pilots. Not only is the G410T unbelievably easy to use and inexpensive, it is also extremely compact.
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