Required instruments and lighting

[Andrew Fay]

Hi,

I finally bought a Comanche. A 62, 250. Now I have a ton of questions. My first set of questions relates to the panel.

I have some redundant engine instruments and I'd like to clean up the panel a bit. I have a mechanical tach and a digital one, mechanical oil temp and press and a digital one, a turn and bank and an Stec autopilot. All of the gauges and instruments are stc'ed and certified as a direct replacements.

So my questions are:
is there any legal reason I would have to keep the old mechanical gauges and the extra turn and bank? If I do remove the tach, what do I do about the tach drive on the accessory case?

I don't have panel lights and liked the nulites on my last airplane, they claim a pilot can legally install them. How does that work? It seems that splicing into the PoT would be an AP type operation.

I would also like to mount a panel dock for my 496 in the old location of the adf. I know the faa considers those " minor" alterations but does that mean a mechanic needs to do a logbook entry or is it considered like interior trim?

Thanks in advance

[md11flyer]

Andrew, If the gauges are STC'D as direct replacements then you do not need to keep them. AS a matter of fact, I don't know what instruments you have, but
for instance Horizon tachs have the stipulation that the old mechanical tach "must" be removed. Also my installation of Aerospace Logic Fuel guage stipulates the old fuel gauges are not
to be used together with the new gauge. My thinking is that most STC'd instruments that are certified as a direct replacement, requires the old instrument to be disable/removed.
You can get a cover for your tach cable from Aircraft spruce, although the installation package for your replacement tach should have come with one.( P/N 10-06754............... $19.99ea)
For the lights just install them when you have your AP handy to inspect your handy work and sign off the log book.
Hope this helps,
Gary

[Andrew Fay]

Thanks for the info Gary,
I just bought the airplane and the gauges were already in it, I'm in ATL right now and I'm going to head to aircraft spruce in the morn and pic up some goodies. Thanks for that part number.


Andy