Falcon/Fahlen Prop

[46j3cub@comcast.net]

is a Falcon prop approved for a J-3 C65

Part #: FALCON PC326CE TC681-585 92-72-44 S/N 1219

[Dave]

Mike Redpath in OKC took over the Fahlin Type Certificates and began manufacturing them under the Falcon name. He posts here occasionally, although hasn't in some time, but he would certainly be the one to ask.

(I have his email and phone number, but I'm not sure his old email address works anymore.)

I couldn't find that Type Certificate number corresponding to another manufacturer, but it certainly looks like it would be the same design as a Sensenich 72C44.

[46j3cub@comcast.net]

Mike Redpath in OKC took over the Fahlin Type Certificates and began manufacturing them under the Falcon name. He posts here occasionally, although hasn't in some time, but he would certainly be the one to ask.

(I have his email and phone number, but I'm not sure his old email address works anymore.)

I couldn't find that Type Certificate number corresponding to another manufacturer, but it certainly looks like it would be the same design as a Sensenich 72C44.

Dave,

Could you please email me his info. Thanks.

46j3cub@comcast.net

Dennis

[ChrisR]

While this thread began almost fifteen years ago, it is still a valid question in 2024. My A&P and I had similar questions when I purchased my airplane. So, I'm adding what I've learned for the benefit of others. If you have additional knowledge - please add details below. These props are perhaps even more obscure now, and they might live for another 15 years.

Nowadays it's possible to search the FAA type certificate database for airplanes (A), engines (E), and propellers (P). Search: Type Certificate Data Sheets for propellers, and the keyword "Falcon" to find a list (table) of Falcon propellers. While the table, doesn't specify applications by aircraft type, it does provide HP, RPM and hub dimensions for each propeller model. It's possible to map an engine's HP, RPM and hub dimensions to a specific propeller model.

It looks as though the above example might have missed a couple of important details, e.g. I believe the propeller model should have been proceeded by a "D." What's more, the "C65" might have been an A65, a common engine on the Piper J3 Cub. Both the Continental A and C series engines have more than one crankshaft variant, i.e. propeller attachment. These details weren't provided.

I'll use my engine/propeller set up as an example below. My engine is a C75-8F. The "F" denotes a flanged crankshaft (vs. tapered crankshaft). The C75/85 TCDS (E-233) and the C75/85 Overhaul Manual include the maximum HP, RPM and flange dimensions for this engine.

My propeller's numbers are: PC326CE-T C681-D585 followed by 90-74-45-SN1066. In my case, D585 corresponds to a propeller model number in the table. The table includes: HP, RPM, prop diameter, prop pitch, # of holes, hole diameter, bolt circle diameter, and hub thickness. These match the flange dimensions described in the Overhaul Manual. My prop has a 74" diameter and 45" pitch. The C75's maximum HP and RPM, provided in the engine's TCDS, are less than those shown in the table. I assume the table shows the maximum HP and RPM for the propeller. Unfortunately the HP and RPM in the table are not fully defined. This makes it impossible to know if this propeller has other applications, e.g. on a C90-12F which has the same flange, but higher HP and RPM.

The table also has a column for "TC." In my case it's 681. The characters on the prop also include "TC 681." I'd guess that TC = type certificate. However, there is no TCDS P-681 in the FAA database. Perhaps this refers to an earlier type certification?

I haven't contacted them yet, but what remains of the Fahlin propeller works is in the Wings of History Museum in Satna Clara, CA. The museum might be able to shed additional light on these rare propellers:

https://www.wingsofhistory.org/the-prop-shop/