Speed of design of airplanes.

"Smartace11" wrote in message
...
was "Get
it done, and in our hands ASAP" with most other considerations
secondary-- would we see a dramatic improvemetn, or just a fwe months
shaved off here and there.

It would be produced in 10% of the time with 90% of the
quality/reliability.
(And at 25% to 50% of the cost. All that oversight is expensive.)



What is the source of your data. The AF has been trying to calculate
those
costs for years to convince Congress to back away a little.

A comparison of what has been done at places like the Skunk Works
(SR-71) and comparable places, and what has been done by
companies on their own dime (F-20); vs standard military
contracts.

Nothing the Air Force comes up with will convince Congress
to back away. That would mean no more "fact finding" junkets,
no more high visibility televised committee hearings, no more
getting their asses kissed by the contractors, and no more
being able to steer contracts to their home districts.

Tony

"SteveM8597" wrote in message
...
In a few words, software, systems integration, changing user requirements,
parts obsolesence and Congressionally mandated funding
profiles/milestones.
Drives a contractor into a risk averse position and long development
cycle.

I have a theory that the westernised industrial culture went to crap the
moment they started teaching Project Management at university, adding
countless levels of bean-counting and overhead to engineering projects.

Si

I have a theory that the westernised industrial culture went to crap the
moment they started teaching Project Management at university, adding
countless levels of bean-counting and overhead to engineering projects.

To a large degree, the engineers WERE the project managers in the 70s and if
you take the F100 engine as an example things really fell apart as the
durabilty and reliability specs were non-existant. Too much new technology and
mainoy just a performance (thrust) spec. A large part of the F-15/F-6 fleets
were grounded due to the stall stagnation issue. Then GE and Pratt were
competed against one another and miracles happened. Also programs became far
more multi-disciplined and program management morphed into an integration role.

The problem isn't ptogram management, it is dealing with all the people who
want a piece of the action all the way down to the Congressional reps who have
one tiny supplier to the prime in their districts, and the ones who MIGHT get a
new base or a base buildup. Defense programs mean jobs and votes so
Congressional oversight is intense, even in semi-black programs. That lead to
far more reviews and requirements management that slow down development and
production.

On 29 Dec 2003 13:40:14 GMT, (Smartace11) wrote:

To a large degree, the engineers WERE the project managers in the 70s and if
you take the F100 engine as an example things really fell apart as the
durabilty and reliability specs were non-existant. Too much new technology and
mainoy just a performance (thrust) spec. A large part of the F-15/F-6 fleets
were grounded due to the stall stagnation issue.

Before that there was grievous trouble with compressor discs flying
apart into a bunch of pieces and trashing the rest of the engine. I
was in the control room for the first MEA of the F-15.

Mary

--
Mary Shafer Retired aerospace research engineer

"Mary Shafer" wrote in message
news
On 29 Dec 2003 13:40:14 GMT, (Smartace11) wrote:

To a large degree, the engineers WERE the project managers in the 70s
and if
you take the F100 engine as an example things really fell apart as the
durabilty and reliability specs were non-existant. Too much new
technology and
mainoy just a performance (thrust) spec. A large part of the F-15/F-6
fleets
were grounded due to the stall stagnation issue.

Before that there was grievous trouble with compressor discs flying
apart into a bunch of pieces and trashing the rest of the engine. I
was in the control room for the first MEA of the F-15.

The F100 engine was also the death of much field maintenance for USAF
engines. The turbine blade inspection failure rate was so high that the
wheels (nearly?) always had to go to Depo for rebalance. Then there was the
pilot's fear of FBW and the remechanisation of the entire F-15 controls
system. All in all, the F-15 was a pretty dynamic target for the designers
to try and hit.

As Steve said, "Systems Integration". The airframe is only a part of the
modern aircraft "system". Factor in the added layers of complexity from
working with the competing and often conflicting cultures and philosophies
of multiple customers and the political influence that assures that every
state/country gets some of the action and it is a wonder that anything gets
from the design stage to actual flight!

Jack

"Charles Gray" wrote in message
...
Here's a question-- why does it take so much longer to design and
protoytpe a plane today? Between the JSF and F-22 literally decades
have gone by.
Now, granted, the JSF is orders of magnitude more complex then say
an F-4...but on the other hand, CAD/CAM tools exist that give design
and engineering staffs tools that are also orders of magnitude ahead
of what was possessed in the 1960's.
So, to the engineers in teh group, are we seeing a problem that is
basedin the designing of the planes, or the process used to create
that design, in the administrative and bueraucratic ways things are
done?

As opposed to when?

It was comparatively easy to design an aircraft in say 1937. All you
had to do was bend some metal, rivet on some aluminium, and send a
brave man up to fly it. If he didn't come back, you went on to another
design. If he did, you could improve it according to his notes. This
is not a valid approach with supersonic aircraft.

But your point is valid. The Word Trade Center was collapsed more than
two years ago, and they're still arguing about the design of its
replacement. Does anybody seriously expect to enter that building on
the 5th anniversay of 9/11? By contrast, the Empire State Building
went from first turn of the shovel to first public occupancy in about
one year.
all the best -- Dan Ford
email:

see the Warbird's Forum at www.warbirdforum.com
and the Piper Cub Forum at www.pipercubforum.com

Cub Driver wrote in message . ..
As opposed to when?

It was comparatively easy to design an aircraft in say 1937. All you
had to do was bend some metal, rivet on some aluminium, and send a
brave man up to fly it. If he didn't come back, you went on to another
design. If he did, you could improve it according to his notes. This
is not a valid approach with supersonic aircraft.

But your point is valid. The Word Trade Center was collapsed more than
two years ago, and they're still arguing about the design of its
replacement. Does anybody seriously expect to enter that building on
the 5th anniversay of 9/11? By contrast, the Empire State Building
went from first turn of the shovel to first public occupancy in about
one year.

Hell...Army CENTCOM is arguing about how to increase protection on
trucks and Humvees in use in Iraq while troops in theater are trying
to buy any kind of steel plate they can get to hang on the vehicle
doors. Policy is getting in the way of protection, and the middle
managers aren't getting their ducks in rows with any measure of
expediency. I'd rather be a civvie contractor with employer-purchased
body armor and personal weapon & wheels than an Army joe right about
now.

"Cub Driver" wrote in message
news
But your point is valid. The Word Trade Center was collapsed more than
two years ago, and they're still arguing about the design of its
replacement. Does anybody seriously expect to enter that building on
the 5th anniversay of 9/11? By contrast, the Empire State Building
went from first turn of the shovel to first public occupancy in about
one year.
all the best -- Dan Ford


The thing to have done for the World Trade Center reconstruction would have
been to build it exactly as it was before. Just the sort of 'in your face'
gesture that would have made a point to terrorists that the USA may bend but
not break.

My opinion,

Tex

"Tex Houston" wrote in message
...

"Cub Driver" wrote in message
news
But your point is valid. The Word Trade Center was collapsed more than
two years ago, and they're still arguing about the design of its
replacement. Does anybody seriously expect to enter that building on
the 5th anniversay of 9/11? By contrast, the Empire State Building
went from first turn of the shovel to first public occupancy in about
one year.
all the best -- Dan Ford


The thing to have done for the World Trade Center reconstruction would
have
been to build it exactly as it was before. Just the sort of 'in your
face'
gesture that would have made a point to terrorists that the USA may bend
but
not break.

The port authority wanted to tear down the WTC, "as it was before".