Main gear stripped out during flight?!

[Paratrooper]

So, I was flying my E-Razor yesterday and actually had it at flying altitude for the first time.  Feeling pretty confident flying "tail in" style.  Traversing left and right showing my nose for brief periods and feeling good with the controls.  Knocking out piros once in a while.  Then at about a 100 ft, I hear a "ratcheting" noise and notice a slight decrease in lift, with an increasing lack of control.  With my heart pounding, I perform emergency landing procedures (a series of "freak out" stick movements) and get her down in a controlled crash with no damage. 
Upon inspection, it turns out that my main gear was completely eaten up by the pinion.  What would cause this?  Was the setup on my "RTF" a little too tight?  That would never happen right? 

I just wanted to get expert input of possible causes to prevent future in-flight malfunctions.  Thanks guys.

[FireballXL5]

Alright, not an expert, but here's my two cents worth. Either the clearance was too big for the gear mesh allowing enough slop that the pinion gear started rounding teeth on the main gear til it failed. Or the motor mount screws weren't loctited, or tight enough that the motor slowly slipped away from the main gear causing eventual stripping. If it's too tight the gears will make more noise, cause more vibration, and wear out the motor and other components faster. Most pilots I've seen adjust their gear mesh with a little slop, or slide a strip of paper between the two gears, tighten the motor with the gears tightly together with the paper between them, then spin out the paper and you've got a little bit of play between the gears.

[mckrackin]

Alright, not an expert, but here's my two cents worth. Either the clearance was too big for the gear mesh allowing enough slop that the pinion gear started rounding teeth on the main gear til it failed. Or the motor mount screws weren't loctited, or tight enough that the motor slowly slipped away from the main gear causing eventual stripping. If it's too tight the gears will make more noise, cause more vibration, and wear out the motor and other components faster. Most pilots I've seen adjust their gear mesh with a little slop, or slide a strip of paper between the two gears, tighten the motor with the gears tightly together with the paper between them, then spin out the paper and you've got a little bit of play between the gears.

Ditto

[Super 6-4]

Well PT at least you got her down in one piece!!! You heard a noise, realized there was a problem and made the correct "crazy stick inputs" to get her down in one peice. Good job, man!!! some of us aren't that lucky or smart!

[Paratrooper]

Thanks for the words of encouragement 6-4


I actually met Mike Durant the original Super 6-4 pilot.  My unit was in Somalia when that whole deal happened.
just some trivia for ya.

[Super 6-4]

A humble honor my friend Thank you and your team mates!!!! God bless you and them all.

[Beachcomber]

Yes I agree, too loose is more likely to strip the gears than too tight.  And too tight causes other problems.