Pipers/Strutural Engineering/Doors

In article . net, Mike
Rapoport wrote:

It adds more weight than you might think. The area around the door has to
be reinforced. Make a paper box and feel how stiff it becomes when you tape
the final side and then cut a jarge hole on one side and note how much
stiffness it loses.

I understand the torsional rigidity issue.
Cessna does it, suspending the fuselage from the wing.
Beech did it with the Musketeer line.
I would think the wing on the bottom would make it easier because the
wing center section spar box and not the fuselage structure is not
carrying the load.
How much weight are we talking about? 25 pounds?
The weight's of Pipers and Cessna's seem pretty comparable across the
product lines.

Is the question more one of economics?

EDR wrote:
In article . net, Mike
Rapoport wrote:


It adds more weight than you might think. The area around the door has to
be reinforced. Make a paper box and feel how stiff it becomes when you tape
the final side and then cut a jarge hole on one side and note how much
stiffness it loses.


I understand the torsional rigidity issue.
Cessna does it, suspending the fuselage from the wing.
Beech did it with the Musketeer line.
I would think the wing on the bottom would make it easier because the
wing center section spar box and not the fuselage structure is not
carrying the load.
How much weight are we talking about? 25 pounds?
The weight's of Pipers and Cessna's seem pretty comparable across the
product lines.

Is the question more one of economics?

I would not be willing to pay 25 Lb in our clubs Archer for a second
door. I find 3 adult men and normal luggage puts me at full GW.

John Roncallo

I would not be willing to pay 25 Lb in our clubs Archer for a second
door. I find 3 adult men and normal luggage puts me at full GW.

True. But with the 1460 pound useful load of our Pathfinder (Cherokee 235)
they could easily have sacrificed 25 pounds of structural reinforcement in
exchange for the added convenience and safety.

I still believe that Piper's decision to forego the pilot-side door in the
235/236 line has proven to be a many multi-million dollar mistake for Piper
over the years.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

How expensive would it have been to get a second door certified? I wonder
why nobody has developed a second door STC if it is so desirable and easy to
do. The whole success of the Cherokee line was based on commonality of
parts and low cost.

Mike
MU-2


"Jay Honeck" wrote in message
news:kXPFb.633938$Fm2.569782@attbi_s04...
I would not be willing to pay 25 Lb in our clubs Archer for a second
door. I find 3 adult men and normal luggage puts me at full GW.

True. But with the 1460 pound useful load of our Pathfinder (Cherokee
235)
they could easily have sacrificed 25 pounds of structural reinforcement in
exchange for the added convenience and safety.

I still believe that Piper's decision to forego the pilot-side door in the
235/236 line has proven to be a many multi-million dollar mistake for
Piper
over the years.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

How expensive would it have been to get a second door certified? I wonder
why nobody has developed a second door STC if it is so desirable and easy
to
do. The whole success of the Cherokee line was based on commonality of
parts and low cost.

Right, but see EDR's post. Who cares how expensive the endeavor is, if it
means you'll sell three times as many planes?

On the other hand, there's no guarantee that a second door would have
guaranteed this result -- but for many "less sprightly" pilots, the single
door is a real handicap.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

Sure they could have sold more *if* the price was unchanged, but what if it
cost $10,000 more? The 235 was never going to sell as well as the 182 or
206 anyway which both have significant utility advantages operating
off-airport and short field.

Mike
MU-2


"Jay Honeck" wrote in message
news:GL%Fb.633459$Tr4.1633242@attbi_s03...
How expensive would it have been to get a second door certified? I
wonder
why nobody has developed a second door STC if it is so desirable and
easy
to
do. The whole success of the Cherokee line was based on commonality of
parts and low cost.

Right, but see EDR's post. Who cares how expensive the endeavor is, if it
means you'll sell three times as many planes?

On the other hand, there's no guarantee that a second door would have
guaranteed this result -- but for many "less sprightly" pilots, the single
door is a real handicap.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

The 235 was never going to sell as well as the 182 or
206 anyway which both have significant utility advantages operating
off-airport and short field.

Well, that's somewhat debatable. If you're talking about landing in
wagon-rutted fields with three-foot hedges on either side, you're right --
the 182's high wing and steel gear will beat the low wing aircraft, hand's
down.

However, it's kind of the aviation version of SUV marketing: Sure, a Hummer
can climb a 60 degree slope, but who really cares? 99.995% of the
population will drive it to the store.

Bottom line: I fly the Pathfinder in and out of grass strips that would
challenge a lesser plane. That's as "off-road" as I care to get. Heck,
that's MORE "off-road" than most pilots I know *ever* get. (D'ja ever take
your MU-2 into Amana? :-)

Sure they could have sold more *if* the price was unchanged, but what if
it
cost $10,000 more?

As I understand it, the 235 was already priced higher than the 182 back in
'74 -- so the chances of Piper coming in with it under-priced were unlikely.
Still, Piper sold enough 235s and 236s to make them a profitable line, and
the second door would only have helped sales.
--
Jay Honeck
Iowa City, IA
Pathfinder N56993
www.AlexisParkInn.com
"Your Aviation Destination"

In article . net, Mike
Rapoport wrote:

Sure they could have sold more *if* the price was unchanged, but what if it
cost $10,000 more? The 235 was never going to sell as well as the 182 or
206 anyway which both have significant utility advantages operating
off-airport and short field.

Don't confuse the issue.
Rough field operations is a prop clearance issue.
That's why the outfitters and bush pilots use taildraggers.
Mooney's aren't the smartest airplanes to operate off of grass strips
unless you know for certain they have no dips or holes.

"Jay Honeck" wrote in message
news:GL%Fb.633459$Tr4.1633242@attbi_s03...
How expensive would it have been to get a second door certified? I
wonder
why nobody has developed a second door STC if it is so desirable and
easy
to
do. The whole success of the Cherokee line was based on commonality of
parts and low cost.

Right, but see EDR's post. Who cares how expensive the endeavor is, if it
means you'll sell three times as many planes?

On the other hand, there's no guarantee that a second door would have
guaranteed this result -- but for many "less sprightly" pilots, the single
door is a real handicap.

'Spose it (the one door affair) ruined the Bonanza as well?

In article kXPFb.633938$Fm2.569782@attbi_s04, Jay Honeck
wrote:

I still believe that Piper's decision to forego the pilot-side door in the
235/236 line has proven to be a many multi-million dollar mistake for Piper
over the years.

Yep, Cessna outsells Piper 2:1 or even 3:1, depending on the model.