Can the GPS collective bump happen in the air?

[rs2k]

When the skookum is ready to fly it gives a collective bump. The GPS makes this process take several seconds longer while it locks onto the sat signals. When the LED on the SK720 turns green after power up in the pits I usually pick the heli up and start taking it to the flying area. Shortly after I pick it up I'll feel the collective bump as the LED turns blue. If I ever forget to check for the bump or miss the color of the LED light before the heli takes off is there a possibility the collective can give a bump in the air?

[Xrayted]

Originally Posted by rs2k

When the skookum is ready to fly it gives a collective bump. The GPS makes this process take several seconds longer while it locks onto the sat signals. When the LED on the SK720 turns green after power up in the pits I usually pick the heli up and start taking it to the flying area. Shortly after I pick it up I'll feel the collective bump as the LED turns blue. If I ever forget to check for the bump or miss the color of the LED light before the heli takes off is there a possibility the collective can give a bump in the air?

There was a report of this happening right after the GPS release. Someone was hovering in their basement, the GPS managed to get a lock after being in the air, and his heli did a surprise pitch pump on him, almost causing a crash.

I seem to remember Art or someone chiming in and saying something about correcting this behavior so this can't happen once airborne, so I assumed this was taken care of in the 1.05 GPS firmware we have now, but who knows

It would be easy enough to test out in a controlled hover. especially on the first power up where GPS lock takes some time.

[sl4ppy]

I almost always take off before the light goes blue and the GPS bump happens; mostly because I'm just impatient.

It's never affected flight at all; ever. i suspect it's too fast to be noticeable, or Art did indeed remove it.

[augur]

Hi.

If you take off too early the barometers are not calibrated correctly. So the GPS height control could malfunction which will set then.

[rs2k]

The answer to it bumping in flight is yes, it can do it. I tested it with the blades of and the bump happened at full RPM.

I won't have to worry about it for a while though. I ejected my GPS module through the tail blades while doing a blur piro today.

Helicopter survived. GPS is long gone.

[Xrayted]

Originally Posted by rs2k

The answer to it bumping in flight is yes, it can do it. I tested it with the blades of and the bump happened at full RPM.

I won't have to worry about it for a while though. I ejected my GPS module through the tail blades while doing a blur piro today.

Helicopter survived. GPS is long gone.

Was it still sitting on the ground though? The unit has an air and ground mode, so I wonder if it would still do it airborne?

Wow, that was one expensive piro to kill your GPS! At lest they are 10% off this weekend during some of the Holiday sales, assuming you can find them in stock anywhere.

[rs2k]

Yup, I thought I stripped a tail gear because I heard a bang during the blur piro. I stopped the piro and put it in TH and auto'd down.

It was pretty far away and I landed in a mud hole, but there was no damage other than the frayed end of the GPS cable. The double sided tape gave. It was strong enough to hold the helicopter up with so I can only imagine the g forces involved. I can see why it's called a blur piro.

[whatevva]

Yup, this happened to me once, and I stripped a set of tail gears with a hard landing. Never again...now I wait patiently for that blue light.....

[Vladconnery]

Happened to me once and it is definitely noticeable. I nearly crapped my pants as I was on a low pass when it happened. No damage just butt cheek clinching time.