Dented Nose Truss

[M20F-1968]

I try to leave my plane at a location where it will not need to be moved.  If I do not trust that the FBO will keep their word that it will not be moved, then 

I use this:

Still does not completely remove the risk of scooper tugs without a turnstyle.  Just need to make sure it is removed before flight.

John Breda

Do Not Tow-1.pdf Do Not Tow-2.pdf

[ArtVandelay]

I had my bent by an FBO yesterday. Let's see if they own up to it.

I can’t see any dent, but I do notice you have the stops I thought would prevent this?

[Tim Jodice]

The stop bolt is bent and opposite the bolt bracket the pipe is bent where the paint is blistered. I couldn't get a good side picture.

The stops help but as many have said with the leverage of a tug connected to a 10 foot universal tow bar it moves the bend/break somewhere else. 

[Davidv]

Related question, are all nose trusses different or did Mooney use pretty much the same one across many models? I’m asking from a replacement perspective rather than different limits.

[Tim Jodice]

3 hours ago, Davidv said:

Related question, are all nose trusses different or did Mooney use pretty much the same one across many models? I’m asking from a replacement perspective rather than different limits.

Newer models came from the factory with stops, replacements from Lasar have them also. As many have said and my experience this weekend they can still be damaged. 

[Mooneymite]

4 hours ago, Davidv said:

Related question, are all nose trusses different or did Mooney use pretty much the same one across many models? I’m asking from a replacement perspective rather than different limits.

Be aware that the modified truss from LASAR may, or may not be exactly for your model/year.  My damaged truss did not need the spacer, but the replacement from Lasar definitely did:

 

[cliffy]

On 2/6/2019 at 7:37 AM, DonMuncy said:

You would be surprised how much it would restrict the turning radius. There is really very little space between the tubes to allow for turning.

 

On 2/5/2019 at 10:38 PM, cliffy said:

I've given some thought to taking a piece of 4130 aircraft tubing (.032 wall) and cutting a piece into an oval shape to glue over the area of the denting. It would provide a little more defense against the dent. Maybe no fool proof but some help. Likewise it would cut the turning radius down a little. 

Given my comment and Don's comment I wonder just how close the tubes get when turning with just rudder pedals? I would think there is some clearance there because if it hit the tubes together every tight turn we'd see evidence of paint or tube damage all the time. Maybe there is .032 clearance  or more under normal circumstances

[DonMuncy]

13 minutes ago, cliffy said:

 

Given my comment and Don's comment I wonder just how close the tubes get when turning with just rudder pedals? I would think there is some clearance there because if it hit the tubes together every tight turn we'd see evidence of paint or tube damage all the time. Maybe there is .032 clearance  or more under normal circumstances

Interesting question. I'm sure somebody know, but I don't.

[bradp]

Who’s got a gear swing coming up?

[cliffy]

Mine is on jacks tomorrow and I'll be looking at this

[cliffy]

On 2/7/2019 at 5:57 AM, mooneyflyfast said:

That's ridiculous.  Last one I replaced was from Lasar rebuilt for about 450 in parts. Exchange, I think. Don't recall the labor but probably a couple of hours should cover it.  EDIT If I couldn't get a rebuilt one, I would take mine to a good welding shop and have the dented section of tubing replaced. This should be legal as an owner produced part. Or, have my mechanic state that it was repaired in accordance with AC 43.13 and it is approved for return to service.

Having it rewelded would be nice BUT what is the heat treat procedure? Do you know if the part is heat treated? I seem to  remember it is but maybe LASAR knows for sure.

What FAA approved data would you use to show compliance with the factory part to be an approved OPP? 43.13 won't cut it alone.  BTW, a REPAIR is NOT an "Owner Produced Part"  It is a "repaired" part by definition.  Having it rewelded  would in no way qualify as an OPP. 

Here's another very good article on OPPs-  Makes for good reading 

https://www.aviationpros.com/home/article/10387511/owner-produced-parts-how-they-affect-maintenance

Secondly as to my posting just above-   I measured the gap between the two tubes in both directions at full pedal throw and find that on mine I have actually over .150 clearance on each side. SO I don't think an .032 "shield" in the contact area would be a big hindrance in the turning radius. May have to look into this more  as I have LOTS of 4130 a/c tubing in the shop.