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Newsgroups: sci.aeronautics.airliners
From: ehahn@fairlite.mitre.org (Ed Hahn)
Subject: Re: Valsan 727 modifications
Date: 22 Mar 94 09:52:41 PST

In article <airliners.1994.1027@orchard.Chicago.COM> jdd@db.toronto.edu
(John DiMarco) writes:

   Anybody care to comment on the financial implications of modifying
   older 727s rather than replacing them outright?

----
Well, for one airline, the financial considerations they undertook
when considering retiring the B727-100 and -200 fleets hinged on three
things:

1) Windshear Detection Equipment retrofit (FAR 121.358)
2) Traffic Alert and Collision Avoidance System retrofit (FAR 121.356)
and
3) Stage III noise regulations (can't recall the exact FAR)

Nos. 1 & 2 were required on all airliners (more than 30 seats) by
December 30, 1993.  The ballpark cost of retrofit per aircraft for
Windshear is 40K(USD), and for TCAS is 150K+(USD).

Number 3, Stage 3, is required in 1999.  Basically, to meet Stage 3
noise regulations, the current engines (JT8D-17s et al) must be
modified in some way, or be replaced.  This, of course, is VERY
expensive (hundreds of thousands to millions of USD).  Earlier posts
regarding the Valsan conversions have detailed what is involved here.

Offsetting the cost is the fact that the B727 can be a very useful
aircraft on some routes.  The airline that I am familiar with operated
125 B727-200s in 1992, and is slowly retiring the older aircraft so
that there will be about 67 of them left by 1997.  The main reason
they are hanging on to them are that they are VERY profitable on
Caribbean routes because:

1) Fairly good takeoff performance.
2) Good payload carrying capacity (-200A version), especially when you
consider that flying over the Caribbean requires HF radios and full
overwater crash survival equipment (rafts, etc).
3) Three engines, which is useful for avoiding some of the hassles of
trying to fly overwater with only two engines in a small aircraft
(i.e. MD80 class).

Therefore, this airline will continue to operate the B727-200 until
1999, when they will retire the remaining 67.  The costs of reengining
and aging aircraft modifications will make further service not cost
effective.  It should be noted that there was some concern at this
airline about which aircraft was going to replace it on these
profitable routes.  BTW, the airline retired the last of its -100s
before the end of 1993.  The reduced payload capacity of the -100 made
it not cost effective for TCAS/Windshear retrofit.

Note that this was the case for only one airline, and that the plan
was pretty firm at the time I left.  Furthermore, this airline was in
good financial shape, and has plenty of brand new aircraft on the
delivery schedule, so they weren't hurting for seats.

Just one point of view...
ed

////////   Ed Hahn | ehahn@mitre.org | (703) 883-5988   \\\\\\\\
The above comment reflects the opinions of the author, and does not
constitute endorsement or implied warranty by the MITRE Corporation.
Really, I wouldn't kid you about a thing like this.



Newsgroups: sci.aeronautics.airliners
From: ehahn@fairlite.mitre.org (Ed Hahn)
Subject: Re: Twin-engine 727?
Date: 13 May 94 11:31:43

In article <airliners.1994.1208@ohare.Chicago.COM> stephenl@de.deere.com
(Lyle E. Stephens) writes:

   A reliable observer reported what looked like a B-727 with only two
   engines at Detroit during the week of April 27. The top engine air
   inlet had been replaced with a fairing, the tail cone had been modified,
   The nacelles were larger than usual, and the landing gear looked
   somewhat different. The plane was in American Airlines colors. The
   observer is familiar with DC9/MD80's. Does anyone know more about
   such a plane?
---------
When I was with AA, the company had looked at a two engine retrofit
for the B727 to prolong aircraft life with Stage 3 noise regulations.
The proposal involved attaching larger nacelle engines (RR Tay or IAE
VR2500?) while putting a hemispherical fairing in the center inlet.

American decided that this wasn't the way to go, and given the
downsizing trend within the airline and the economics of the existing
fleet, they probably haven't changed their minds.

However, AA has also retired quite a few B727s over the last couple of
years (mostly various -100s, but at least 10 -223/-2A7s by last
January).  When they left the airline (from the Tulsa maintenance
facility), they had the tail logo and the "American" on the fuselage
removed, and had the red fuselage stripe repainted blue (thus yielding
Blue-White-Blue fuselage stripes). However, it was very apparent to
anyone looking at them who they had belonged to.

My guess is that one of the buyers of these retired aircraft has
decided to try installing the engine retrofit, finally.  I'll defer to
someone else to answer the other half of this question...

Later,
ed

////////   Ed Hahn | ehahn@mitre.org | (703) 883-5988   \\\\\\\\
The above comment reflects the opinions of the author, and does not
constitute endorsement or implied warranty by the MITRE Corporation.
Really, I wouldn't kid you about a thing like this.



Newsgroups: sci.aeronautics.airliners
From: ehahn@bass.mitre.org (Ed Hahn)
Subject: Return to Lessor story (was Re: Long term storage)
Date: 15 Feb 95 03:42:21

In article <airliners.1995.174@ohare.Chicago.COM> stevep@shell.portal.com
(Steven H Philipson) writes:

      It may seem crazy to have a 100 million dollar airplane
   just sitting there (especially when the financing is running
   $20,000 per day), but it can be the cheapest alternative for
   the airline.  This is a big-bucks business.  What seems like
   huge amounts for individuals is all just part of the game
   they're in.

====
Pardon me for changing the subject, but I have a story along these
lines from a couple of years ago...

I was working for an air carrier which had a run-out B747-100 to
return to a leasing company.  However, the terms of the lease said
that four overhauled engines needed to be returned on the wing
(probably particular engine serial numbers).  The airline did the
numbers, and determined that it was cheaper to buy the airframe (which
was out of time), rather than to put the aircraft into return
condition.

So they bought it, and THEN put it immediately into storage, because
they couldn't pay for the aging aircraft modifications to return it to
revenue service.  I suspect that it will never carry passengers again.

Go figure.

ed

--------   Ed Hahn | ehahn@mitre.org | (703) 883-5988   --------
The above comment reflects the opinions of the author, and does not
constitute endorsement or implied warranty by the MITRE Corporation.
Really, I wouldn't kid you about a thing like this.



Newsgroups: sci.aeronautics.airliners
From: drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard)
Subject: Re: Shuttle aircraft
Date: 09 Nov 94 00:51:23

In article <airliners.1994.1663@ohare.chicago.com>,
Still Searching . . . <sr001b@uhura.cc.rochester.edu> wrote:
>About 2 weeks ago, I flew ROC -> BOS via LGA.  I flew the USAir Shuttle from
>LGA-BOS.  The inside of the seemed to be nice many years ago when it must
>have been new but the years have taken their toll.  Why is this aircraft
>still the most popular on this route?  Why not switch to a more economical
>Fokker 100 or soemthing during off-peak hours?

Never having had the pleasure of flying that route, I don't know what
airplane is being used.  That makes it just slightly more difficult to
comment knowledgeably on your question.  Would you be kind enough to
elaborate a bit?  And include the airplane type?

Since having full control of the facts has never kept me from commenting on
the industry in general or in particular, I thought I'd toss out a couple
of possibilities.  First of all, most Fokker 100s will have to be purchased
new at about $22 Million (US).  A very nice 737-200 Advanced or 727-200
Advanced can be gotten for less than a quarter of that, maybe only ten
percent (depending on gobs of variable like certified gross weight,
avionics, engine type and time, maintenance condition, etc).  That $16
Million saved can by a *lot* of fuel and maintenance.

Terry


--
Terry
drinkard@bcstec.ca.boeing.com
"Anyone who thinks they can hold the company responsible for what I say has
more lawyers than sense."



Newsgroups: sci.aeronautics.airliners
From: drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard)
Subject: Re: 707 airframes (Re: Date of Construction)
Date: 01 Apr 94 13:11:48 PST

In article <airliners.1994.1086@orchard.chicago.com>,
John DiMarco <jdd@db.toronto.edu> wrote:

>drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard) writes:
>
>>The DC-8 has shown much better economics over the long haul.  Fewer
>>ADs, fewer aging fleet maintenance requirements.  But, all of that came at
>>a price.
>
>I'm not quite clear exactly why this is so. What exactly about the 707 makes
>it less economical than the DC8?

The 707 is a lighter airplane than the trusty DC-8, structurally.  That
means that it requires a good deal more effort to keep it airworthy.  The
707 is also subject to more corrosion than the DC-8.  Given the higher
costs of keeping the '07 in the air, and what may well be higher systems
maintenance costs, it doesn't pay to reengine it in most instances, for
instance.

Terry


--
Terry
drinkard@bcstec.ca.boeing.com
"Anyone who thinks they can hold the company responsible for what I say has
more lawyers than sense."



Newsgroups: sci.aeronautics.airliners
From: drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard)
Subject: Re: 747-400 mods (was: 737-plus?)
Date: 10 Jul 93 02:01:40 PDT

In article <airliners.1993.505@ohare.Chicago.COM> jge@cs.unc.edu (John Eyles) writes:
>In article <airliners.1993.498@ohare.Chicago.COM> kls@ohare.Chicago.COM (Karl Swartz) writes:
>>Meanwhile, the 747-400 is receiving modifications including a
>>redesigned composite dorsal fin fairing and fuel distribution system
>>which will allow a 2,000 lb increas in MTOW.  The changes will be
>>integrated into new production 747-400s and will be available as a
>>retrofit for existing 747-400s.
>
>Can this be for real ?
>
>I know that in the airline industry, weight is money; but can this be worth
>the trouble ?
>
>It allows another 10 or so pax, or another ton of fuel.  I assume (maybe
>incorrectly) that number of passengers is limited more by seating space
>than MTOW, so we're talking another ton of fuel.

For short missions (under 3,000 miles or so) you are correct, it doesn't
really matter.  One runs into problems at the longer ranges with high load
factors (ie, lots of bodies in those seats).  That extra weight can make
the difference in whether the airplane can be directly dispatched to a
destination, or must use redispatch procedures.  It can make the difference
in whether the flight must be diverted or can go straight in (winds).  But
add the extra weight and combine it with new electronics and software that
give the airplane the ability to seek out the most efficient route, and
you've added significant capability to the airplane for a modest
investment.

You might also keep in mind that one seat can add several million dollars
in revenue to an airline.

>I believe these babies consume about 10 tons of fuel an hour at cruise,
>so we're talking 6 more minutes of flight or about 50 nm.
>
>How much can this retrofit cost and be worth it ?

Depends on who you are.  Literally.  :-)




--
Terry
drinkard@bcstec.boeing.com
"Anyone who thinks they can hold the company responsible for what I say has
more lawyers than sense."



Newsgroups: sci.aeronautics.airliners
From: drinkard@bcstec.ca.boeing.com (Terrell D. Drinkard)
Subject: Re: 747-400 mods (was: 737-plus?)
Date: 16 Jul 93 03:21:40 PDT

In article <airliners.1993.513@ohare.Chicago.COM> Mike@oscar.demon.co.uk
writes:

>In article <airliners.1993.508@ohare.Chicago.COM>
>drinkard@bcstec.ca.boeing.com writes:
>
>).  That extra weight can make the difference in whether the airplane can be
>directly dispatched to a destination, or must use redispatch procedures.
>
>Can you explain the difference between these procedures for me please?

Maybe.  :-)
In a direct dispatch, the airplane has a flight plan filed for the
advertised destination.  It is the simple, uncomplicated case, and works as
you would expect.

In redispatch, the flight plan is for some destination closer than the
advertised one.  And not neccessarily in the same direction as the
advertised destination (there maybe some 30 or 40 degrees difference).  The
airplane will fly towards its advertised destination, and if the winds are
favorable, it will file and updated flight plan and land at the advertised
destination.  If the winds are bad, it will continue on to its *planned*
destination, with Captain Speaking telling the passengers of the
unfortunate diversion for fuel.  The dispatcher and the pilot have figured
out where the decision point for that flight is, and the pilot (and the
dispatcher) make the decision based on fuel remaining and projected fuel
requirements.

Is that sufficiently obscure?  :-)


--
Terry
drinkard@bcstec.boeing.com
"Anyone who thinks they can hold the company responsible for what I say has
more lawyers than sense."


Newsgroups: sci.aeronautics.airliners
Date: 10 Feb 2000 05:03:17
From: David Lednicer <dave@amiwest.com>
Subject: Re: Good 'ole 727

Richard Isakson wrote:
> It couldn't meet stage three noise requirements

So it seemed, but Raisbeck has managed to get light and medium weight
727s to meet Stage 3 with simple changes to the flap and slat
schedules.  For heavier weight 727s, exhaust mixers must be added, but
the aircraft still meets Stage 3.

> There was no way to keep the wing wake out of the engine inlets and,
> on a high by-pass engine, that caused a compressor stall.

So it would seem, but Douglas managed to get V2500s to work on the MD90
(V2500s and CFM56s were the engines often considered for 727
reengining).  How did they do it?  While we're on the subject, the
Valsan reengining with JT8D-209s works quite well.

I think there is another ingredient to what killed the 727.  A 727-300
was offered in the mid-1970s.  It would have had stretched fuselage,
JT8D-200 engines, a modified wing and four wheel leg landing gear.
United showed interest, but in the end declined to order it.  This led
Boeing to develop an all new aircraft, which became the 757.

-------------------------------------------------------------------
David Lednicer             | "Applied Computational Fluid Dynamics"
Analytical Methods, Inc.   |   email:   dave@amiwest.com
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