Bruce Fenstermacher wrote:...David's airplane is the airplane that I think we could use to show Cessna build and delivered at least one 170 with an illegal engine according to the TCDS.
Perhaps, "...with an improperly documented engine according to the TCDS." ...might be a polite way to say it..???
I recall that my own airplane with an O-300-C and EM7655 prop was issued it's original Airworthiness Certificate by FAA after FAA had inspected it for re-Import-Airworthiness. When I brought that to the attention of my FSDO the inspector there corrected me when I suggested the FAA had approved a technically "illegal" engine... he stated it wasn't "illegal" per se... only "improperly documented". While my paperwork (which they'd issued) made it legal to operate, I bought the Massicot (now Assoc'n) STC just to dot the "i" and cross the "t" for both engine and EM7655 prop. I didn't want some persnickety inspector making a big deal of it surprising me by grounding the airplane.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention. An originality nut (mostly) for the right reasons.
Thanks Bruce I'll try to remember this, I knew that it was a renaming but thought that the purists would know the minutiae of the changes and the corresponding dates. So safe to say only the later B models would have had the lever and prop, unless the engine was subbed later in the aircraft's life like mine was.
Question......does anybody know a better way to re-size pictures for the forum without cropping half the picture out?! I see on the post worksheet there is a tad that says "resizeimg" But I can't get it to do anything.
-2H engines had a controllable pitch prop capability. Not constant speed but you could change the pitch with a lever in the cockpit.
That engine would allow you to swing an Aeromatic propeller with he High Cruise feature but...that propeller is no longer supported by anyone. The current owner of the Aeromatic prop doesnt suport the High Cruise prop.
An Aeromatic propeller uses air loads and centrifugal force to change position, not hydraulics, so it will work on any engine it will bolt onto.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
-2H engines had a controllable pitch prop capability. Not constant speed but you could change the pitch with a lever in the cockpit.
That engine would allow you to swing an Aeromatic propeller with he High Cruise feature but...that propeller is no longer supported by anyone. The current owner of the Aeromatic prop doesnt suport the High Cruise prop.
An Aeromatic propeller uses air loads and centrifugal force to change position, not hydraulics, so it will work on any engine it will bolt onto.
The one approved for the 170 is the High Cruise model which uses oil pressure from the crankshaft to override the automatic pitch setting at altitude for better performance. That’s why the TCDS requires the -2H engine to be installed for that prop.
The more common Aeromatic prop is not approved for the 170.
That's the way I understand it also, but the problem is Aeromatics are no longer supported and the last TCDS-owner surrendered his certificate so Aeromatics are orphans. They are also subject to wood-rot at the lag-bolts which hold the blades and an AD note in that regard. While the Aeromatic always seems to hold interest for those seeking better performance... in reality, it's not viable because it's not available. I've flown behind an Aeromatic (in a different airplane) and it was very disappointing. (Admittedly not the model approved for 170s) It surged unexpectedly at some flight attitudes and it wasn't easy to determine if any performance advantage actually existed due to lack of comparison opportunities. Short-version: Forget about Aeromatics. IMO
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention. An originality nut (mostly) for the right reasons.
Awwwww......not such a beautiful thang. The intersection where the vertical stabilizer meets the horizontal stabilizer. Pulled the acces panel and was greeted with this ominous sight. Remember....the rudder was not on the plane for years and the rudder spar has all those inviting perfectly bird sized holes. Keeping fingers crossed...... drilling rivets.
Ok........vertical and horizontal stabilizers removed. This is looking at the bottom of the vertical stabilizer. Oblivious that birds made nests in there......but this damage is surely from rat/mouse urine. Birds typically don't pee and poop in their nests so..... drilling out rib now to see how far the damage goes. If anybody has one of these lower end ribs for sale....I'm your guy!!! Lol.
Lower rib removed. Was able to get most of the straw out of this bay. The one above it had a little as well I had to fish out. Pressure washed it al thoroughly and thankfully, it appears that MOST of the damage was limited to the rib. The spars look great!! Whew. Dodged a bullet here. "Might" have to change one side skin. But won't know until I scotch Brite and acid etch everything.
Never a good sign when you can easily poke a screwdriver through a corrosion spot. This Is the bottom side, center section of the horizontal stabilizer. Drilling off panel now. Stay tuned.
-2H engines had a controllable pitch prop capability. Not constant speed but you could change the pitch with a lever in the cockpit.
That engine would allow you to swing an Aeromatic propeller with he High Cruise feature but...that propeller is no longer supported by anyone. The current owner of the Aeromatic prop doesnt suport the High Cruise prop.
An Aeromatic propeller uses air loads and centrifugal force to change position, not hydraulics, so it will work on any engine it will bolt onto.
The one approved for the 170 is the High Cruise model which uses oil pressure from the crankshaft to override the automatic pitch setting at altitude for better performance. That’s why the TCDS requires the -2H engine to be installed for that prop.
The more common Aeromatic prop is not approved for the 170.
Well, I learned something today; I wasn’t aware that there was an Aeromatic prop with hydraulic assist.
Approved or not, I have seen 170’s with the regular Aeromatic prop installed.
Miles
“I envy no man that knows more than myself, but pity them that know less.”
— Thomas Browne
Safe to say that horizontal stab is scrap, time to hunt one down...I think the George or the Mock family had some in crates some time ago, maybe George Horn knows where they landed up.
Drilling off panel now. Stay tuned.