Hi there!

I've been instructing for a gentlemen who owns a C170A with a 220 Franklin (Hartzell Constant Speed Prop). The prop spinner is starting to crack and the mechanic recommends flying without it until we're able to find a replacement. Unfortunately, used spinners run around $3000, and a composite shop quoted $6k for a new one.

Does anyone have experience with this or know if the prop spinner required Eq? I looked in the Type Cert, Engine STC, and have not been able to find any statement requiring it.

Thanks for any info!

Stick+Rudder wrote:Hi there!

I've been instructing for a gentlemen who owns a C170A with a 220 Franklin (Hartzell Constant Speed Prop). The prop spinner is starting to crack and the mechanic recommends flying without it until we're able to find a replacement. Unfortunately, used spinners run around $3000, and a composite shop quoted $6k for a new one.

Does anyone have experience with this or know if the prop spinner required Eq? I looked in the Type Cert, Engine STC, and have not been able to find any statement requiring it.

Thanks for any info!

I would say that if the STC does not require a spinner then a spinner is not required.
The TCDS will be of little value as the motor/prop/spinner are not listed.

$6,000 to make a new spinner "composite"? Im guessing that means fiberglass or possibly carbon fiber? With the old spinner to make the mould, you could owner make that part 250 times for that price.

Would/could there be any effect on cooling airflow

There's a guy in Denver that hand spins spinners. Has quite a inventory...Beeches, Cessnas, Pipers, and customs. None of them are 337'd or otherwise papered. Quite a few of them flying. Bulkheads too.

lesuther wrote:There's a guy in Denver that hand spins spinners. Has quite a inventory...Beeches, Cessnas, Pipers, and customs. None of them are 337'd or otherwise papered. Quite a few of them flying. Bulkheads too.

Sounds like an owner made part to me.
Provide the spinner as a template, inspect the product and have your A&P install the part.

Do you have a number for this guy in Denver? I actually need a spinner as well.

I bet that's a hoot to fly. Like many airplanes of that era I felt it just needed a little more power to realize its full potential. And dihedral.

Anyway, to be 100% legal, you'd need to look at the STC to see what it specifies. Wag Aero sells a 170B spinner. It says it's a PMA'd part for certain 170Bs and 172's. This is probably what's on there already. This is the "bullet" spinner as compared to the "skull cap" spinner that was original on the early ones. This picture from the Franklin website shows a bullet style spinner that looks a lot like the one I had on my C-145 powered 170A. (Sometimes you see a pointy one from a later model 172 or 180). If that thing has been on there for long time, I'd just find one like it and go with that. I guarantee you it didn't come from Hartzell or Cessna. It probably came from a salvage yard or a catalogue parts house.

Bagarre wrote:Do you have a number for this guy in Denver? I actually need a spinner as well.

A-1 spinning
303-534-5667

Denver art district.

Most of the airplanes I flew had no spinner.

Check the p/n of the spinner or the p/n of your prop,
and check with some propeller shops.
Some of them get a lot of trade-ins, or props that can't / won't be repaired,
often ncluding spinner.

If a spinner from a 170 with a c-145 would work let me know would sell it cheap since it needs work and backing plate proceeds Z and this site

My backing plate cracked. I actually only saw it when I was reinstalling it. I was lucky enough to find one from another member on the 170 forum, the Spruce price was $336 I think just for the bulkhead.

There was a complete spinner for sale on the 170 forum about two months ago.

lesuther wrote:

Bagarre wrote:Do you have a number for this guy in Denver? I actually need a spinner as well.

A-1 spinning
303-534-5667

Denver art district.

That number goes to a massage school or something. I tried googling a different number but nada.

Moss Farmer, Do you still have that spinner. I am looking for a new one.

Jon "Jughead" Counsell
Snohomish
850-seven23, two zero 72

Will take a photo of it and pm you with the photo

whee wrote:

lesuther wrote:

Bagarre wrote:Do you have a number for this guy in Denver? I actually need a spinner as well.

A-1 spinning
303-534-5667

Denver art district.

That number goes to a massage school or something. I tried googling a different number but nada.

That's an odd way to drum up massage business!

Cary

TM Technologies....The Tin Man. Not sure how swamped he is... nobody better than Kent White. Course I may be a bit prejudice...
https://www.tinmantech.com/

PM sent.

The spinner is most likely mandatory from a legal standpoint, but you'll need the installation instructions for the STC to verify that. Hopefully you have the installation instructions with the aircraft's maintenance documentation. That's the only way to verify your aircraft's "properly altered configuration" as well as verifying the ICA's for the Franklin install.