Jack wrote:
> I have a 1946 Ercoupe 415 C/D . . . I can't figure out why it is
> not an E model.
Jack,
Lets start at the beginning.
Here are the possible model numbers:
415-C
415-CD
415-D
415-E
415-F (stripped down model, very few made, all converted, I think)
415-G
There is no such thing as a 415-C/D.
Note that Type Certificate Data Sheet A-787 does allow a 415-C or 415-CD
to be up-converted to be a 415-D. No other changes are authorized.
(Well, I guess you could legally change it back but that'd be crazy as,
due to the wording of the Sport Pilot regs, the plane would not be able
to regain its Light Sport Aircraft eligibility.)
If you have a 415-C or 415-CD, then it only allows a maximum gross
weight of 1260 pounds, or, if you have the STC, 1320 pounds.
If you have a 415-D, E, or G, or Forney F-1, then you have a maximum
legal takeoff weight of 1400 pounds. The penalty of having your plane
converted to be a D (or later) model is that it loses about $10,000 in
value as it may not be flown with a Sport Pilot or PPouSPp acting as
pilot in command. (PPouSPp = Private Pilot operating under Sport Pilot
privileges.)
(Forney F-1A, Alon A-2 and Mooney A-2A or M-10 models all are allowed
1450 pounds gross weight with, essentially, (Mooney M-10 excepted) same
airframe. However, note that the Forney, Alon and Mooney models all
came with the C-90 engine.)
If you do have a 415-C or 415-CD, then its nice that it has the
modifications that give you more convenience and features and, in the
case of the split elevator, slightly greater safety. In no way does it
need to be a higher model unless you want to carry 1400 pounds (in which
case you lose that extra $10,000 in market value). Each of those mods
can be separately approved for a 415-C or 415-CD.
Youll note that the models which ARE allowed to carry 1400 pounds are
structurally almost identical to the 415-C and 415-CD with only minor
tweaks in the airframe including either limiting the standard elevator
to 9° up travel. The Split elevator gets the same job done with even
greater safety (as it returns the touch down speed to the original
designed touch down speed).
Theres no doubt Marv does know his stuff. Me, I did not fly outside
the front or back of the envelope even inside the gross weight limits
and absolutely so if outside the gross weight limit.
In the Coupes case, the designers thought that the original 415-C
deserved to carry 1400 pounds. But, the FAA was being very, very
careful writing regulations for this unprecedented two control,
certificated as spin proof aircraft. I think youll find that the
primary difference in gross weight is regulatory, not aerodynamic or
structural.
As for taking your sons for a ride:
160 yourself
250 son
915 aircraft
====
1325 empty weight less fuel
75 pounds fuel / 6 = 12.5 gallons
12.5 gallons 6 gallons reserve = 6.5 gallons or 72 minutes at 5.4 gph.
(For putting around, maneuvers, pattern work my actual burn was about
4.5 gph but I planned local flights based on 5.4 gph, my 2400 rpm cruise
fuel burn.)
So, if youve got a 415-D (or later), you can certainly take them for an
1-hour long flight.
If you have a 415-C or 415-CD, youre right, your sons cant go for a
ride till they lose weight or you decide to bust the gross weight
limits.
Ed
