It's an FAA conformity thing. Procedure requires the
aircraft to reflect what is aproved by ATC 724. A
200hp engine installed on a M62A (PT-19A) C/N airframe
becomes a M62A-3 or -4. Literally take your pick on
the dash number. To redesignate the aircraft as an
M62A-3 does not make it a real PT-26. It is still a
PT-19. Add the canopy, it's still a PT-19. It's
approved equipment according to ATC 724. Remember,
we're talking about an aircraft in civil use in 2003,
not an aircraft in military use in 1944. Also, try
not to apply the military S/N to all this. The C/N is
the reference while the military number is only a
historical thing.
On the difference between a M62A-3 or a -4. None,
nada, zip. The designation was determined by a
purchase contract issued from the government. It was
their way of keeping track of procurement. It is
still done this way.
Now for the engine. The civil designation 6-440-C5 is
the 200hp engine while the military identified it as
the L-440-3 or -7. There are several carburetors
approved for use on the engine. The military
identified the engine with different dash numbers for
the carburetor installed. There are other appliances
approved for use on the engine but they do not affect
the dash number. In civil use, the 6-440-C5
designation does not change. It can use either a
Bendix or Stromberg carburetor. But one must make
sure that the correct intake manifolds are used for
the carburetor installed.
I just referenced my Air Britain BAC Lend-Lease book.
I noticed that two contracts worth of Fleet built
Cornell II's (PT-26A) have AAF S/N's!!! Regarding the
PT-19's to the Columbian government, I would say the
200hp engines were installed because of operations at
bases above 5,000 ft.
Now for the kicker. Does a PT-19 with a 200hp engine
have better performance than one with a 175hp? No.
It dosen't make any difference what-so-ever.
Hope you're not thoroughly confused by all this !
Mike
--- tonyb42uk wrote:
__________________________________> Mike,
> You raise an interesting point. I understand what
> you say about
> redesignating as a M-62A as a M-62A-3/4 when fitted
> with the 200 hp
> Ranger. In fact it was Joe who first explained this
> to me when I
> asked him why there were so many examples with PT-19
> c/nos.
> designated as M-62A-4.
>
> Historically, the M-62A-3 and M-62A-4 designations
> applied to the
> various PT-26 variants and so I had been mystified
> as to why a
> number of aircraft with PT-19 manufacturer's serial
> were listed in
> the US Civil Register, in effect, as PT-26's. I
> seem to recall your
> father saying this was required when the the PT-19's
> engine was
> replaced with a Ranger 6-440-C5 model or the engine
> upgraded to that
> standard.
>
> What I am still unclear about is what was the
> original difference
> between the M-62A-3 and the M-62A-4. It would easy
> to assume one
> type number applied to the Fairchild-built PT-26 and
> the other to
> the Fleet-built PT-26A/B, but this does not appear
> to be the case.
>
> To quote ATC-724 -- "The M-62A-4 is identical to the
> M-62A-3 and
> both are the same as the model M-62A except for
> engine." If they
> are identical, why the two designations? Does the
> difference lie in
> the actual model of Ranger engine fitted?
>
> The PT-26 'Take-off & Landing Chart' and 'Flight
> Operation
> Instruction Chart' in T.O.No. 01-115GA refer to
> "Engine Models L-440-
> 3, -7"
>
> So what was/is the difference between the L-440-C3
> and the L-440-C7;
> -- vacuum pump, generator,or perhaps the carb?
> Might this have some
> bearing on the M-62-A3/-4 designations?
>
> Would appreciate your thoughts on this.
>
> As an aside, the USAAF records of some of the twelve
> late model PT-
> 19A diverted to Columbia in 1944 refer to an engine
> change to 200 hp
> and the fitting of auxillary tanks, presumably to
> aid the ferry
> flight.
>
> Regards, Tony Broadhurst
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