Transition from 172 to 150

Ever notice that the wings of all of the high-wing, strut-braced Cessna models of the early 1970s were modified with the rounded "Camber-Lift" leading edge -- except the 150/152 and 207?

The 207 is easy enough to explain; it was a low-volume item and not worth the expense of flight test and certification. But the 150 ...

Cessna engineers fitted a 150 with the modified leading edge for test flight. Said Cessna Manager of Flight Test & Aerodynamics Bill Thompson,
" ... [A]ll flying qualities and performance checks proceeded routinely. Then came spins. Right out of the box, a 2-turn spin took 13 turns to recover! Variations on the full-span camber-lift airfoil, such as an outboard-droop-only and increased wing twist, were tested, and unacceptable spin behavior was noted. During this period thousands (literally) of spins were conducted on the C-150 without ever having to resort to the safety equipment."

Cessna engineers were also leery of the aftermarket 150 hp STC for the C-150, that put the heavy battery box in the back of the airplane, resulting in a tendency to a flatter spin attitude.
 
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One thing that I cant figure out and the CFI just gave me a blank stare was this.....What is it?
 
A venturi for your gyros. CFI should have known.

So would this take the place of the vacuum pump? I ask because the preflight check list under the suction guage heading we were NOT in the green arc .... we were at 2.something. He said it wouldn't be higher until airborne. I never did look back over at it but I did notice the heading indicator and the artificial horizon were giving me inaccurate readings....

Is this a common issue with a venturi like this?
 
Your lucky the C150 is only $85/hr. At my airport it is $115 for the c150 and $140 for the 172. If it was only $85/hr for me I'd definitely use my schools 150.
 
Your lucky the C150 is only $85/hr. At my airport it is $115 for the c150 and $140 for the 172. If it was only $85/hr for me I'd definitely use my schools 150.

Well, just rent it for a half hour?
 
So would this take the place of the vacuum pump? I ask because the preflight check list under the suction guage heading we were NOT in the green arc .... we were at 2.something. He said it wouldn't be higher until airborne. I never did look back over at it but I did notice the heading indicator and the artificial horizon were giving me inaccurate readings....

Is this a common issue with a venturi like this?

Yes, they are an alternative to an engine driven vacuum pump.

They do require a bit of airspeed before they pull enough vacuum to adequately spin the gyros. I can't quote you an amount.
 
A key item noted above is "smaller". I have 4.1 hours in a 150 from my student pilot days and don't plan on increasing that number. With the seat all the way back my knees are in the panel when I go for the brakes. Watch your W&B, the full fuel payload isn't al that great in a 150. Also, it's the only plane I've flown where traffic on I-5 was passing me. :)
 
Your lucky the C150 is only $85/hr. At my airport it is $115 for the c150 and $140 for the 172. If it was only $85/hr for me I'd definitely use my schools 150.

This is the main reason I'm sticking with it...
 
Recently the FBO where I usually rent from has added a older 150 to the rental fleet. I have done all of my training and renting in a 172N and 172I. What should I expect to be different in transitioning into the 150 other than the obvious size differences? I am trying to maintain flying every week to two weeks and this addition will reduce the rental cost for these 1 hour flights from 130/hr to 85/hr. Scheduled for checkout tomorrow morning.

Don't bring a passenger.
 
When I took lessons, the C-150 was $10/hr and a 172 was $15.

And the airplanes were a lot newer then, too! I paid $19 for a 172 in 1973. It was a whole six years old at that time.
 
So would this take the place of the vacuum pump? I ask because the preflight check list under the suction guage heading we were NOT in the green arc .... we were at 2.something. He said it wouldn't be higher until airborne. I never did look back over at it but I did notice the heading indicator and the artificial horizon were giving me inaccurate readings....

Is this a common issue with a venturi like this?

Venturis were abandoned in favor of vacuum pumps. Venturis are draggy. They don't generate enough vacuum until you're in the climbout. They ice up.

But they last a lot longer than a vacuum pump.
 
If you bought a new Cessna 172 before 1961, and wanted gyro instruments in it, you had venturis. The O-300-C engine did not have a pad for a vacuum pump. One of the features of the optional “Skyhawk” package, introduced in 1961, was an O-300-D engine with provision for a vacuum pump.

Base-model 172s, without the “Skyhawk” option package, had the O-300-C, and venturis, through the 1967 model year.

Likewise, a vacuum pump was an à la carte option on that late-‘60s 150, without the top-of-the-line “Commuter” option package.
 
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