The Twin Commander as a Traveling Machine

[donv]

The thing about fuel caps, especially on 690s, is that the tabs can wear out and the cap may seem to be locked down, but actually isn't. Then the low pressure on top of the wing sucks the cap right off, probably around rotation.

When I was flying for Aero Air in the early 2000s, we had a real problem with the center tank fuel caps on our 690 fleet. We typically did short legs, and rarely put fuel in the wings, but the center caps were opened and closed at least once a day.

Eventually, I think they bought some new caps and started rotating the caps at the 150 hour so they all got used more equally.

[Adam Frisch]

Speaking of fuel caps, mine are of the old "need to use a screw driver or quarter to open them" model. Basically they suck at being easy to use. I inquired to have them replaced with more modern tab-operated replacement but where told none existed. Only option was to change the whole inlet/attachment part and cost was eye-watering. I guess the market is just too small to make a modern fuel cap as an STC'd product.

[donv]

Mine are that way too. Are there any Commanders which don't have those sort of caps? I've never seen one.

Speaking of fuel caps, mine are of the old "need to use a screw driver or quarter to open them" model. Basically they suck at being easy to use. I inquired to have them replaced with more modern tab-operated replacement but where told none existed. Only option was to change the whole inlet/attachment part and cost was eye-watering. I guess the market is just too small to make a modern fuel cap as an STC'd product.

[Steve binnette]

I looked into it awhile ago.  I remember it being about $3000 a side of you could find any of the new style. Naples jet center did locate some.  They were the type of caps with a flip up tab that rotated.  Much better.

I just did not think it was worth it.  So I bought a spare fuel cap I keep In the plane in case one gets lost along with a couple of stubby screwdrivers I pass out.

[Adam Frisch]

I looked into it awhile ago.  I remember it being about $3000 a side of you could find any of the new style. Naples jet center did locate some.  They were the type of caps with a flip up tab that rotated.  Much better.

I just did not think it was worth it.  So I bought a spare fuel cap I keep In the plane in case one gets lost along with a couple of stubby screwdrivers I pass out.

Yeah, those. I don't know what the deal is with those, but when Morris was alive he also said they were almost impossible to get your hands on. Did the manufacturer discontinue them or something?

Seems to me that it should be a pretty straightforward STC to develop.

[donv]

I personally prefer the standard kind. I have a screwdriver in the baggage if the line guy doesn't have one, it's easy to see if they aren't closed properly (since the little screw thing stands up), and they just work.

Other than not needing a screwdriver, what is the advantage of the other kinds of cap? I found in my Baron and Aerostar that those caps can wear out and leak, which is another issue.