The International Cessna^® 170 Association

Hello all,
I think I have finally decided to install the Sportsman’s stol kit. A question came up and I was reaching out for any guidance. For some reason I have the 195 style Pitot tube. A couple mechanics have mentioned if I’m going to install the cuff, now is the time to install the normal 172 Heated pitot tube. I’m sure it’s easier to install the cuff with the 172 style, anyone aware of any performance issues??
Thanks Mike

I have the 172 version on mine with sportsman STOL STC. Works great.
John

Mike,
I'm hoping Richard will chime in here as he wrote this several years ago:

hilltop170 wrote: ↑Sun Feb 01, 2009 8:35 pm Anyone thinking about using the Kollsman pitot needs to know that there is non-standard calibration required on the airspeed indicator if the Kollsman pitot is used. It will indicate fairly accurate at low speeds but will read too high at cruise if the non-standard calibration is not done. This has caused problems for 195 owners and is why Aspen did not include the 195 on the AML for their new electronic EFIS

I was thinking that Richard was saying that a calibrated correction card -- like we all have for the whisky compass -- was necessary when using the the masted Kollsman pitot tube but it appears to me that a special airspeed indicator is necessary. If this is correct, I don't understand why it is not included in the drawings (#0511051) for the installation of that heated pitot tube. Fig. 45-7 of the 190-195 IPC list two different airspeed indicators, depending on serial number. Through s/n 16083 they use the masted pitot like you have. The airspeed indicator to go with these early 195's was p/n 0311015-3. S/n 16084 and on used the "L"-shaped pitot tube and airspeed indicator 0311015-4. According to Garmin a software update,

Approved a new airspeed calibration curve for the Textron Aviation (Cessna) 190 and 195 series aircraft. This airspeed calibration allows the GI 275 to replace Cessna 0311015-1 or 0311015-3 (Kollsman Type 586CK-0187) airspeed indicators.

So, it seems that we need to buy airspeed indicators which then need the correct markings added, or switch to the L-shaped pitot, or buy a GI-275.

I wonder if the calibration issue is due to the different static port -- on the C-195 they use the static port on the pitot tube -- or is it the pressure (pitot) side that's necessitating a different airspeed indicator? If it's the static side, it seems that one could just use the boot cowl static port, cap the static port on the pitot tube, and use our existing airspeed indicator.

Thanks John any chance you have a picture.? Just curious where it's mounted. Is it on the inspection panel right by the strut?

Wow Gary thanks! I think you just put me over the edge to just go back the L shaped. I hope Richard chimes in. But I'll search for that post in the meantime. I mean a 275 would be nice!

We did the install per the service kit directions in a 172E. Fairly straightforward. Finding the heated pitot and the element for the stall warning took the longest.

Wxbee wrote: ↑Wed Jan 22, 2025 10:52 pm … Just curious where it's mounted. Is it on the inspection panel right by the strut?

AK175-23D shows the mounting location. Station 65.12 is 8” outboard from the rib at the outboard end of the fuel tank.

Good copy I see that now thank you!, having a harder time convincing the mx that this is doable!

Wxbee wrote: ↑Wed Jan 22, 2025 6:29 pm Hello all,
I think I have finally decided to install the Sportsman’s stol kit. A question came up and I was reaching out for any guidance. For some reason I have the 195 style Pitot tube. A couple mechanics have mentioned if I’m going to install the cuff, now is the time to install the normal 172 Heated pitot tube. I’m sure it’s easier to install the cuff with the 172 style, anyone aware of any performance issues??
Thanks Mike

WHOO-HOOO! THAT is the CORRECT ORIGINAL style heated pitot for a 170…and is quite rare to see. KEEP IT! (or, since you plan to take the airplane off “original” status with a STOL kit)…..donate it to the Assoc’n for others who may covet it. Contact me for instructs on how to donate it.)

Sorry didn’t mean to lean ya hanging! What I do to destroy the originality of it I sure hope I make up by keeping the ‘harpoon’! I had a great conversation with Mr Pulley and i decided to keep it a Harpoon ship! I didn’t realize how unique of a setup it was. Thanks again for all the help! For those that haven’t followed attached is a pic of the mighty Harpoon Ship!