Garmin

Bartman

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Mar 27, 2018
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as I understand it, if the unit is TSO'd it can legally be installed in any certified aircraft with a 337 form that references the TSO. a TSO is a more broad authorization than an STC which is airframe specific.

did I get that right Bob?
 

Bob Turner

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Apr 4, 2018
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1,259
I don't think so. TSO is only a form of "part" approval. "This item meets applicable standards."

A radio does not need a TSO, at least under part 91. Usually, a different radio is considered a minor alteration - a logbook entry.

Other than the strange ADS-B application, the 337 is limited to major repairs and alterations. A valid 337 must cite "approved data". A TSO is not approved data - it is more like a manufacturing and sale approval.

Caveat - there are folks who know this stuff better than me - I pay attention, but I do not always have the correct answer.
 

Bob Turner

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Here is an example: wheels are TSO'd. The Scout has somewhat limited choices for wheels, brakes, and tires. I forget the details, but if you have a 6:00 Cleveland TSO wheel, you cannot simply slide it on and be legal. It has to be within the part number series approved for that aircraft.

Cub guys go through this. You cannot remove the 8:00x4 wheel and brake and replace with 6:00x6 TSO Cleveland. You also need to purchase the STC for the alteration.
 

Big Ed

N50247 - '79 Super D
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Jul 20, 2020
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387
Location
Tampa, FL
My avionics shop recently installed a Garmin 225 in my Decathlon with the following logbook entry:

Installed Garmin GTR225 p/n 011-02718-00 s/n xxxxxxxxx in radio stack at frame station # -6.0. Installation done in accordance with Garmin installation manual p/n 190-01182-02 Revision H, dated September 2017. Determined not to be a major alteration.
 
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Tangogawd

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Sep 13, 2020
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34
Location
Alaska
Same, I install as logbook entry. Local avionics shop sells me GTR 200, to save a few bucks. TSO not required for part 91. They did say that IF the plane was IFR (radio required), they want to see ONE TSO radio. They said back in the day non of the radios installed in IFR planes had TSOs.
 

Big Ed

N50247 - '79 Super D
Joined
Jul 20, 2020
Messages
387
Location
Tampa, FL
Have about 75 hours XC since I installed my GTR225 a few months ago. Really great radio. Flip-flop and standby monitoring are essential features. Display is very legible in daylight and night, even for old eyes like mine. For whatever reason I seem to have developed radio anxiety after a 10 year break in regular flying, and the Garmin helped me work thru that. Last night I flew from Hope, AR to KWPA, a Class B embedded in joined Class C for OKC and Tinker AFB. Lot going on between multiple airspaces, flying over downtown lights, and my first night flight in 15 years. Turned out to be a non-event, but having a good quality radio lowered my stress level going in.

PXL_20201117_232559295.jpgPXL_20201118_011503019.NIGHT.jpg
 

Goodyear

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Oct 24, 2019
Messages
272
Nice pictures! Always fun that first night landing in a new taildragger-is the landing light pointed anywhere that matters? Congrats on a good trip.
 

Big Ed

N50247 - '79 Super D
Joined
Jul 20, 2020
Messages
387
Location
Tampa, FL
I replaced the old landing light with a Whelan LED the day before the trip. Also replaced the wiring harness in the lower cowl, which was worn halfway thru from contact with the accessory pulley. It is pointed where it needs to be for approach and roundout. Really like LED lights; the added reliability and performance is well worth the cost. I did about 4 hours at night on my recent trip, and appreciated the confidence of not having to worry about burned out bulbs.