Mystery Aircraft Quiz #9

[Pilawt]

While we're on the subject of Champion aircraft ...

We know that the original Aeronca 7AC Champion qualifies under the new Light Sport rules. American Champion Aircraft Company recently announced they are considering a new Light Sport version of the Citabria line, with a 100-hp Continental O-200.

But there is nothing new under the sun. In 1971-73 Bellanca Champion built a bare-bones Model 7ACA "Champ" (photo below), which with its 1220-lb gross weight and low performance would have met LSA criteria.

The question is ... what was unusual about the 7ACA's factory-installed engine?

-- Pilawt

 

[SCCutler]

No electrical system accessories?

It was a Franklin?

It ran on perfume?

 

[Pilawt]

It was a Franklin?

Yes, it was a Franklin ... 60 hp ... and in one respect different from any other engine installed in a certified, factory-built US airplane over the past 65 years or so. (If I told you the model number of the engine, that would give it away.)

-- Pilawt

 

[SCCutler]

No starter? I remember this plane, they were selling it for something ridiculous like $7,995.00 or such. I am stuck on the electrics thing, so I am gonna say, no electric starter option.

 

[Pilawt]

No starter? I remember this plane, they were selling it for something ridiculous like $7,995.00 or such. I am stuck on the electrics thing, so I am gonna say, no electric starter option.

The base price was an even more ridiculous $4,995.00. There was an electrical system option. Whether it included a starter I'm not certain, but that's not what I'm looking for.

Hint: The pilot report of the 7ACA in the 1971 Flying Annual said that the inside of the engine compartment "would be a great place for a spare tire."

 

[Henning]

Yes, it was a Franklin ... 60 hp ... and in one respect different from any other engine installed in a certified, factory-built US airplane over the past 65 years or so. (If I told you the model number of the engine, that would give it away.)

-- Pilawt

60hp Franklin? it would have to be a 2 cylinder engine.

 

[Pilawt]

60hp Franklin? it would have to be a 2 cylinder engine.

YES! Two (count 'em) whole cylinders!

In a four-stroke engine that's what, one combustion event for each revolution of the propeller. Can't you just see the pilot saying to himself, "... 2148 ... 2149 ... 2150! Whaddya know, that tachometer is accurate!"

Many 7ACA's have been retrofitted with Continental O-200's, the same engine that American Champion contemplates putting in its new LSA (and which was in the original 7ECA Citabria in 1964).

-- Pilawt

 

[Henning]

YES! Two (count 'em) whole cylinders!

In a four-stroke engine that's what, one combustion event for each revolution of the propeller. Can't you just see the pilot saying to himself, "... 2148 ... 2149 ... 2150! Whaddya know, that tachometer is accurate!"

Many 7ACA's have been retrofitted with Continental O-200's, the same engine that American Champion contemplates putting in its new LSA (and which was in the original 7ECA Citabria in 1964).

-- Pilawt

I used to run a boat with 2 sutzer engines, max RPM...130. 12,000 hp each, but only 130 rpm, you do the math to figure the torque.

 

[Pilawt]

I used to run a boat with 2 sutzer engines, max RPM...130. 12,000 hp each, but only 130 rpm, you do the math to figure the torque.

More than two cylinders, I reckon. Otherwise there might be some vibration issues!

 

[Henning]

More than two cylinders, I reckon. Otherwise there might be some vibration issues!

inline 7s, you could still count out the rpms pretty accurately. Actually, it idled at 130 rpm as well. It uses a controlable pitch prop and as you add load, it adds fuel without changing rpm (unless you use emergency power accelleration then it would drop 10 rpm until it caught up).

 

[gismo]

I used to run a boat with 2 sutzer engines, max RPM...130. 12,000 hp each, but only 130 rpm, you do the math to figure the torque.

Yeah, the cylinders were probably big enough to double as crew quarters when the engine was caged.