PT20J

The M20J has a wing area of about 175 sq ft. (actually a little less because this area includes the area under the fuselage, but this is close enough for this analysis). The weight of snow varies with water content, but lets consider wet snow which is about 20 lb per cubic foot. So, a foot of wet snow will put a downward force on the wings of 175*20 = 3250 lb. The negative load limit is -1.5g, but this is really a factor of 2.5 since there is normally +1g acting on the wings in flight. So the wings can withstand a downward force of 2.5*2900(gross weight) = 7250 lb. The horizontal stabilizer has an area of 21.5 square feet, so a foot of wet snow will create a downward force of 430 lb. So, what will probably happen is that the airplane will end up sitting on the tail tie down. When I used to fly to Truckee CA for a day of skiing I would often see all the tied down airplanes sitting on their tails.

This drawing is for the control installation. The drawing @Slick Nick posted is the correct drawing for the induction system installation. The gasket shown on the control installation drawing is likely an error, but the fact that it does not have a reference number indicates that it is not part of this drawing. The purpose of the drawings in the IPC is to identify parts; they are representational and not actual assembly drawings. I don't recall there being any gasket there when we replaced my engine. But, as always, if there is any question, contact Frank Crawford at the factory because he has access to the actual manufacturing and assembly drawings. I would be very careful about adding a gasket that has any significant thickness. The clearance between the cowling and the lower metal air baffle is minimal and if the baffle is pushed forward it can damage the fiberglass cowling.

That’s the Mooney part number. The Rochester part number is on the back side of the gauge.

It's a typo, I should have said that the Parts Manual does NOT show a gasket... Sorry for the confusion.

Which Rochester part number?

Parts catalog does show a gasket between the air induction assembly and the flange assembly or between the flange assembly and the servo. Probably someone made a gasket on yours.

I'd try drilling it out and and re-tapping.

I always check with my wife

I called Rochester Sensors (current business name) back in May 2024 and talked to Cheryl Manning. She said that they would not sell retail -- I would have to order from a distributor. Attached is the distributor list she emailed me. The hitch is that you have to know the part number which is not the number on the dial face but is (in)conveniently located on the back of the gauge. Someone posted that 5404S02105 is the part number for the M20J gauge. Referral List.pdf

Drew, I'd describe it as an "off white" with a light beige tint. I don't think it looks as brown as the picture you posted. Of course everyone's taste is different, but there is a lot of surface area in that small cabin and the purer whites tend to look very bright -- like you are sitting inside a refrigerator . Colors don't always look true online. If you can find an auto parts or paint store that carries the product it should have the actual color chip chart which is more accurate. You can always buy a couple of different cans and spray some test panels.

Interesting -- I'm only familiar with the Archer wingtip antennas. I've never seen a Archer belly mounted antenna. A VOR antenna would be a dipole and not need a ground plane. If you installed it according to his instructions, then it's probably working as well as it's going to work. I'd be interested to see the installation if you have a picture.

According to the instructions, the Archer VOR antenna must be grounded to the metal skin of the wing (it's designed to be mounted in a wingtip) and it uses the wing nav light wiring as part of the antenna, so I don't know how well it would work mounted in the belly. https://www.aircraftspruce.com/catalog/avpages/archer_antenna-1.php

Frank Crawford at the factory will know for sure. Fcrawford@mooney.com

How large is the ground plane?