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LML: Here is the latest explanation of how Andair deals with the locking screws on the gascolator connections. I'd like to toss a challenge to the group to find a simple solution to this weak link. I would be happy to replace the Andair unit with a metal body, cartridge style, fuel filter with standard fittings similar in strength to the fuel lines. none of the high performance vehicles seem to use the Andair style, they use robust, solid, mountable, aluminum bodies with standard fittings. However, I'm certain there are issues for bypass, flow, pressure drop and so forth. If someone has an alternative that has been reviewed that's the simplest answer. The integrity of our fuel lines and fittings disappears once we insert this Andair device which is protected only by 2 o-rings and 8 small, non-locking screws.
Paul
Legacy
On 2013-06-05, at 10:51 AM, Andair <andair@andair.co.uk> wrote:
> Dear Paul,
> When we offered the feature of being able to move the primary fitting almost 20 years ago now,( remember this only applies to EF20,FF20,FF20-A, FF25and EF25 all other fittings are stagged here in the factory) it was considered to be very useful for the builder.It was then up to the builder or inspector that was signing off that part of the build to establish as to whether the screws had been securly fixed either loctite or damaged into the vacant half hole.
> To "stag" the countersunk screw is a recognised proceedure. We, at Andair, cannot loctite the screws in as there is no visual evidence that the screw is locked in a position therefore it is damaged to show.
> The problem comes as I see it when no third person carries out an inspection and writes it in the log book that it has been checked. On the aircraft I have built where it is considered to be a critical fuction or area e.g. engine controls, fuel systems, flight controls etc there is a section in the log book that is required to be signed. This may not be foolproof but it goes some way to offset these types of problems.
> Lastly when the aeroplane has been built flown a while and then sold on, inspecting everything can be very teadious.
> I hope you manage to read this and it be of some help.
>
> Kind Regards
> Andy Phillips
>
> ----- Original Message ----- From: "Paul Miller" <pjdm@slx.ca>
> To: "Andair" <andair@andair.co.uk>
> Sent: Wednesday, June 05, 2013 10:25 AM
> Subject: Re: gascolator failure
>
>
> I'm looking at a couple of installations here and I can't see any that have incorporated the "stagging". I'll ask the other Legacy owner here to check his screws and see if they have backed off at all. Thanks for that update. It would seem a more certain style of lock is preferable. Your banjo fittings on the fuel selector are safety wired. If the countersunk screws had cap screws with drilled heads, they could be safety wired in place and would never cause this problem. Dumping fuel into the engine area must not have a risk. "stagging" does not appear to be a common practice or one that works particularly well in this case. Andair might want to consider a safety upgrade on the design.
>
> Paul Miller
> On 2013-06-05, at 4:38 AM, "Andair" <andair@andair.co.uk> wrote:
>
>> Dear Paul,
>> When a Gascolator or Fuel Selector is dispatched from the factory with female fittings, the fittings are just pushed on the body and a screw pack complete with Allen key is supplied in the box.
>> The reason for this is when the builder wants to position say a 90deg or 45 deg fitting it never tightens at the correct angle, so in all other cases it is overtightened or is too slack. So, in our case the fitting can be taken off and arranged at 90deg increments, thereby establishing the correct torque on the fitting. Andair suggest that the fitting then be "stagged" (the countersunk screw holding the fitting to the body be damaged to prevent the screw "backing out" there is a small half hole in the fitting for that purpose) If this function cannot be carried out then Loctite should be used.
>> Regards
>> Andy Phillips
>>
>>
>> ----- Original Message ----- From: "Paul Miller" <pjdm@slx.ca>
>> To: <andair@andair.co.uk>
>> Sent: Tuesday, June 04, 2013 6:03 PM
>> Subject: gascolator failure
>>
>>
>> we have a failure on this gascolator. removed for a stuck cup, the firewall side was missing three screws and about to fail catastrophically. Staining evident under the shroud. Missing screws do not appear to be locked and remaining screws are loose and not locked either. Photos are at :
>>
>> http://s1284.photobucket.com/user/pjdmiller/library/andair%20gascolator%20failure%20Lancair%20Legacy
>>
>> Suggest this is a major issue for other aircraft, looking for some guidance, probably SDR submission or more. This is an engine fire waiting to happen if other units are in the same condition.
>>
>> Paul Miller
>> Florida
>> N357V=
>
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