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Info Bolt
Hello, can you help me ...

I am new to Mosquito, I buy an XE285.

I have a problem, I have a screw of the main head to change ...

Problem when I look at the plans the only indication I have is: the screws are 7/16 x 5 / 2M, nut AN 7/16, washer 7/16.

I am in Europe in Belgium, unfortunately I do not measure well the Bolt AN ...

I am looking for Aircraft spruce, no way to understand ...

You know, helped me?

Thank you .

 Here is the picture of the pieces  :

[Image: 1541277588-2018-11-02-li.png]
Hi Titta,

Welcome to the forum and to the best, nicest to fly, most fun for the $$ helicopter in the world...

According to the build manual those are 5-1/2” (5.5”) long Grade 8 SAE 7/16”-20 UNF bolts which are shortened to 5-1/8” long as described in paragraph 9.2 C) of the manual.

However, they are “commercial” quality bolts and the unthreaded bolt “grip” does not pass through all parts of the hub in accordance with normal aviation engineering practice. That’s not to say they aren’t strong enough, they obviously are quite sufficient.

The alternative, which a purist might prefer, would be AN7-51A bolts with MS21044N7 (AN365) nuts and two NAS1149F0763P (AN960-716) washers (one under the head and one under the nut).

AN7-51A is not an easy bolt to find in Europe, but have them and will happily ship by FedEx from the USA.

On paper, AN bolts have slightly lower ultimate tensile stress than SAE Grade 8 (125,000 vs 150,000 psi) but they actually have equal or higher tensile and shear strength due to their UNJF thread form and grip length, and better fatigue resistance, and more stringent inspection standards.

I wouldn’t change the SAE bolts for AN just for the sake of it, but whenever you’re removing and re-fitting blades (e.g. for transport) you might as well use new hardware, so that could be time to fit new AN bolts.
The big problem, how difficult it is in Europe ...

I have a hard time understanding what I need to order ...

Just to help me you would not have a reference, which allows me to order facially!

Here we work in metric and it is very difficult to understand the AN ...

A big thank-you .
Sure, send me an email or call me tomorrow (in English or French). My contact details are on our airfield website,
[Image: 1541331302-2018-11-04.png]

Here is what I order ...

Thank you
It is not necessary to replace all the hardware when you remove the blades for transport, you can reuse all of it. If you remove the nuts them quite often then replace them -

I have a bolt that the net is damaged, I order the bolts AN751A is correct in replacement?
(11-05-2018, 02:09 PM)Titta Wrote: I have a bolt that the net is damaged...

Mike, you probably guessed, but "filet" (in French) can mean "net" or "thread", according to context Smile

And thanks for the tip re. the hardware. I also inspect and replace as necessary, only if in doubt it does it go in the trash.
We've been cooresponding by email -

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