Chris Smith

My Feedback: (2)

I posted this on another thread, but it occured to me others might want to check it out.

While range testing my Futaba FASST on my giant scale bipe, I was able to cause failsafe simply by putting my body between the airplane and the TX. In other words, I turned my back to the airplane. This was at range check low TX power and 100 paces. As soon as I turned and faced the model it recovered( throttle failsafe set to idle). I did it 5 or 6 times with the same result and at all 4 quadrants. I am now trying this at different distances to see what the trends are.

How much fluid do we all contain? I wonder what would happen if I was flying next to a really fat guy? [X(] I'm fat too, so chill.

Chris

causeitflies

The human body is mostly water...

Jim Cattanach

Mines is mostly beer, especially in the summer.

Silver182

My Feedback: (2)

Hi Chris,
The body blocking at low power is the first thing everybody discovers! We all walk away from the airplane when doing a range check...most of us don't walk backwards for long distances) That also concerned me... until I tried full power. You'll note the blocking disappears at full output. Also think about a real world flight scenario.

How do we stand when flying. I'll bet you never fly facing away from your aircraft.. Nope you always are looking at and facing towards your airplane! The only other scenario I can think of might another pilot or person on the flight line walking or standing in front of you.. Not very likely of that happening without you reacting to clear your line of sight, even with a 72MHz radio.

Onboard volumes of fluids or heavy metal are thought to be potential problem, but a good real world human body free-range check will answer those questions for you.

Lee H. DeMary
AMA 36099

Dustin Buescher

At the JWM this year, we put 3 people in front of scott harris' TX for the ground range check. between 80-100 paces, with the button pressed on the 10x module. This was engine running on his Sabre, never fail-safed....

squirt!

I have a similar problem, Mine's full of SH!%... except its all the time. Not a seasonal problem.

Silver182

My Feedback: (2)

I have range checked the Specktrum AR9000 (one remote receiver) with my 10X, Specktrum DX-7, and a Futaba Fasst system 6 channel radio. On low power they all range check in a very similar manor. I reset the radios fail-safe in each case to low throttle position rather than our normal shutdown fail-safe setting. This makes testing the range check limits very easy.. Just throttle up to 1/2 throttle or more and just listen for the fail-safe throttle down.. then turn or walk back in to recover the R/F link.

Walking away from and holding and pointing the transmitter away from the aircraft on low power, my (not so small body) does seem to blank out the signal at very similar distances (more than 60 paces) with all the above tested radios. As soon as I turn 10 -15 degrees left or right R/F link is re-established. With full power this blocking does not seem to occur at very great distances.

Never tried transmitting through three other people as I never asked three guys to walk out with me...might be hard to get that kind of help)

In my opinion body blanking is no range or flight safety factor... it just is part of the 2.4 world.

I have done some full range full power, range checks early on with my DX-7. That test was done with one person sitting in his van holding transmitter out the window... and me driving down a line of sight road to a distance of 1.2 miles. The DX-7 receiver was in an airplane in the back of my Bronco. Windows all up. A very solid R/F link until I would go down into a lower spot in the road, low enough so I couldn't see his van. A that point fail-safe occurred.. Stayed locked out until I came back up to line of sight of his van. R/F link quickly re-established, re-established going away at more than 3/4 a mile.

Bottom line 2.4 is the only way to go...waiting for my Futaba 14 channel conversion)
Lee H. DeMary
AMA 36099

quist

My Feedback: (198)

I know of guys flying foamies with the tx behind there back showing off and going into failsafe mode.

I also believe that range checking the plane to see failsafe is an improper test. I like a range test that shows when you start to drop frames. Your plane will go out of synch with the tx long before it actually hits a enough lose for a failsafe/hold condition.

If you moved one surface up and down and look for the surface to hesitate, I think you would find the range is shorter with people in front of the transmitter.