Cherokee 235 vs Trinidad vs Comanche

On 17-Jan-2007, Ray Andraka wrote:

I believe it. The dakota has the tapered wing where the 235 does not.
In the case of a PA32, the tapered wing adds about 200lbs to the
empty weight.


Hmmm. If I did my numbers right, that's about 1.2 cubic feet of
aluminum. Seems like a lot of aluminum.

Well, the tapered wings are a few feet longer, the fiberglass tip tanks
are replaced with a second set of aluminum tanks, and who knows what
else was changed on the airframe to accommodate the tapered wings. The
point is the tapered winged models run about 200 lbs more than the
hershey bar winged models.


In the PA-28 evolution there were two factors that affected empty weight of
a given model. One was wing length (not necessarily tapered vs.
Hershey-bar) and the other was cabin length. As many have pointed out, in
the early '70s the various models (except the 140) each got a stretch of
about 5 inches in addition to longer wings. Taken TOGETHER the two changes
typically increased empty weight by between 130 and 180 lbs. HOWEVER, most
of the increase was offset by corresponding increases in MGW. Performance
didn't really suffer too much because of the higher L/D of the longer wings.

Here are some examples, with weights from Piper's technical specs:

Arrow 200 (short cabin, short Hershey-bar wing); Empty weight 1459, MGW
2600, useful load 1199
Arrow II (stretched cabin, short wing); Empty weight 1523, MGW 2650,
useful load 1137
Arrow III/IV (stretched cabin, long tapered wing); Empty weight 1637, MGW
2750, useful load 1113

Cherokee 235D (short cabin, short Hershey-bar wing); Empty weight 1467, MGW
2900, useful load 1433
Pathfinder (stretched cabin, long Hershey-bar wing); Empty weight 1592, MGW
3000, useful load 1408
Dakota (stretched cabin, long tapered wing); Empty weight 1608, MGW 3000,
useful load 1392

Note that a change (between Pathfinder and Dakota) from Hershey-bar to
tapered wing only resulted in a 16 lb change in empty weight.

Also note, of course, that these empty weights reflect airplanes with no
"optional" equipment like radios and other goodies, so typical empty weights
will be higher

-Elliott Drucker