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If The MD-90 Had Larger Wings  
User currently offlinelat41 From United States of America, joined Jun 2004, 478 posts, RR: 0
Posted (2 years 1 month 4 weeks 1 day 23 hours ago) and read 15727 times:

It was late in the game for McDonnel Douglas, but if they had the funds, would a larger more modern wing than the MD-80 series have offered, a higher service cieling, more range, better field performance? Might any of those have translated to more sales before Boeing snuffed the model out? The order book was pretty thin by then in any case.

51 replies: All unread, showing first 25:
 
User currently offlineDeltaMD90 From United States of America, joined Apr 2008, 7972 posts, RR: 51
Reply 1, posted (2 years 1 month 4 weeks 1 day 23 hours ago) and read 15726 times:

I could be wrong, but I think the DC-9 series pitfall was always the 5 abreast seating. Had they gone 3-3 I think the DC-9 would have eaten into the sales a bit more.


Ironically I have never flown a Delta MD-90 :)
User currently offlinequickmover From United States of America, joined Mar 2004, 2494 posts, RR: 0
Reply 2, posted (2 years 1 month 4 weeks 1 day 16 hours ago) and read 15032 times:

I love 5 abreast seating.
Less middle seats. What do you like about 3 by 3 seating?


User currently offlineAntoniemey From United States of America, joined Dec 2005, 1601 posts, RR: 4
Reply 3, posted (2 years 1 month 4 weeks 1 day 14 hours ago) and read 14748 times:

Quoting quickmover (Reply 2):
I love 5 abreast seating.
Less middle seats. What do you like about 3 by 3 seating?

Ah, but see, it's not what we like about 3x3, it's what the airlines like. By widening their base fuselage enough to squeeze in a 6th seat per row, Boeing was able to make an aircraft in the same size class as the competing Douglass/MD model that fit 20% more passengers. This then translated to a per-seat advantage in operating costs... which wasn't an issue until deregulation, but then began the game of counting every single penny for each flight... and passengers have consistently voted with their wallets that they'd rather endure a middle seat than spend the extra 10 dollars for a 2x3 plane to make the same amount per flight as the 3x3 plane.

Still, there is a sweet spot for the 2x3 profile where it works better than a very short 3x3, but MD made the mistake of not improving their models enough to keep them really competitive vs Boeing and Airbus, and eventually lost the battle. In many ways an MD-88 is still the same plane as an early DC-9. The MD-90 and 95 were too little too late.



Make something Idiot-proof, and the Universe will make a more inept idiot.
User currently offlineDeltaMD90 From United States of America, joined Apr 2008, 7972 posts, RR: 51
Reply 4, posted (2 years 1 month 4 weeks 1 day 14 hours ago) and read 14732 times:

Quoting Antoniemey (Reply 3):

Was this really why MD lost against the 737? I've read this somewhere before, and it makes sense, but I'm not sure if there were other factors that killed the DC-9 series...



Ironically I have never flown a Delta MD-90 :)
User currently offlineAntoniemey From United States of America, joined Dec 2005, 1601 posts, RR: 4
Reply 5, posted (2 years 1 month 4 weeks 1 day 14 hours ago) and read 14699 times:

Quoting DeltaMD90 (Reply 4):

Was this really why MD lost against the 737? I've read this somewhere before, and it makes sense, but I'm not sure if there were other factors that killed the DC-9 series...

I won't claim to know enough to be able to name every factor, but I know that it was definitely one of them.



Make something Idiot-proof, and the Universe will make a more inept idiot.
User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 6, posted (2 years 1 month 4 weeks 1 day 13 hours ago) and read 14363 times:

Quoting lat41 (Thread starter):

It was late in the game for McDonnel Douglas, but if they had the funds, would a larger more modern wing than the MD-80 series have offered, a higher service cieling, more range, better field performance?

Of course it would have made a huge difference. And the unfortunate reality is the funds were there. Contrary to popular a.net belief, MDC were very profitable in the mid-80's through early '90s. The MD C-level simply got complacent with the MD-80's success and didn't allow R&D the investment that was needed to complete the most vital upgrade. Later, funds were poured into trying to save the MD-11, but it was too late.

Classic conservative mismanagement, Ala GM circa 2004-07. Unfortunately, Clinton didn't bailout MD and implement and mandatory corp restructure to save the company.   

Quoting lat41 (Thread starter):
The order book was pretty thin by then in any case.

Not true. The fact is the MD-90 had more firm orders two years after EIS than the MD-80. The MD-80 went on to sell nearly 1,200 frames...

Quoting DeltaMD90 (Reply 1):

I could be wrong, but I think the DC-9 series pitfall was always the 5 abreast seating. Had they gone 3-3 I think the DC-9 would have eaten into the sales a bit more.

I don't think so. There were numerous studies done in the 1980's that concluded that passengers preferred the 2x3 seating arrangement. Some were publicly funded, others were jointly funded by Boeing and McDonnell Douglas. I recall one survey (circa 1983?) where the results on passenger comfort placed the MD-80 at the highest in the industry. Within days MDC adjusted their marketing materials and proposal data. Coincidentally, within the year, MD-80 sales began to take off.



There's nothing quite like a trijet.
User currently offlineDocLightning From United States of America, joined Nov 2005, 20246 posts, RR: 59
Reply 7, posted (2 years 1 month 4 weeks 1 day 13 hours ago) and read 14365 times:

Quoting DeltaMD90 (Reply 4):
Was this really why MD lost against the 737? I've read this somewhere before, and it makes sense, but I'm not sure if there were other factors that killed the DC-9 series...

Yes, that is how. The big advantage to rear-mounted engines is FOD protection. When the 727 and DC-9 were being designed, there were still a lot of semi-prepared smaller airports that were in use and FOD was an issue. Also, some of the smaller stations couldn't reach all the way up to a 707 fuselage with their airstairs or unload luggage from a plane that tall, so the DC-9 and 727 were put close to the ground, which meant no under-wing engines (until Boeing figured out how to squeeze them under there on the 737.

But it turns out that 3x3 is more efficient because it gives you 20% more passengers in a plane of the same length for less than 20% extra drag. It also turns out that under-wing engines are the most efficient arrangement. The 737 was just the better design.


User currently offlinegigneil From United States of America, joined Nov 2002, 16347 posts, RR: 85
Reply 8, posted (2 years 1 month 4 weeks 1 day 12 hours ago) and read 14033 times:

That's not why per se. The MD-90 carries almost as many passengers as a 737-800. It even does so quite efficiently.

The issue is the lack of capability and the crazy systems problems that plagued both the MD-90 and the MD-11.

NS


User currently offlineTSS From United States of America, joined Dec 2006, 3070 posts, RR: 5
Reply 9, posted (2 years 1 month 4 weeks 1 day 12 hours ago) and read 13912 times:

Quoting lat41 (Thread starter):
It was late in the game for McDonnel Douglas, but if they had the funds, would a larger more modern wing than the MD-80 series have offered, a higher service cieling, more range, better field performance?

I seem to remember reading more than once that the DC-9 and longer MD-80/MD-90 wings are remarkably efficient as they are, so I'm not sure there is big room for improvement on that front. They are definitely highly loaded which translates to a smoother ride during turbulence.

I've wondered if a bigger problem for McDonnell-Douglas wasn't the hole in their lineup between the DC-9/MD-80 and the DC-10 once the DC-8 began winding down in orders. Picture if you will a DC-8 with redesigned wings and two engines instead of four... the McDonnell-Douglas equivalent of a 757.



Able to kill active threads stone dead with a single post!
User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 10, posted (2 years 1 month 4 weeks 1 day 11 hours ago) and read 13508 times:

Quoting TSS (Reply 9):
I seem to remember reading more than once that the DC-9 and longer MD-80/MD-90 wings are remarkably efficient as they are,

The wings were very well engineered and ahead of their time. Aerodynamically, the MD-80 wing was superior to the 727 and 737 classic. I remember this being a selling point in MD proposals, which included: wind tunnel data, diagrams with different flight conditions, and various statistical analysis to support the claims.

All that said, if the MD-90 had a newly designed wing as the 737NG had, it's production run may have lasted a lot longer.

Quoting gigneil (Reply 8):
The issue is the lack of capability and the crazy systems problems that plagued both the MD-90 and the MD-11.

The system problems are a bit exaggerated in the demise of these types. With the MD-11, it was mainly the initial performance shortcomings. AA is really the only airlines that comes to mind that complained on system functionality.
For the MD-90, it was timing. Only 2 years after EIS did Boeing acquire MD. And talks originated while the MD-90 was getting certified. It never had a chance.

But back to the system issues: It's ironic that DL (the airline that worked with MD to design the MD-90) was pained most by it's operational issues; and long after EIS. The level of support dropped to a standstill post-merger, hurting the cause. But it's a wonder TechOps couldn't fine tune the operating procedures a little quicker. Now, it's not even a footnote.

By comparison, JD also had a fleet of 16, of which were operating effectively in 1999.



There's nothing quite like a trijet.
User currently offlineTomFoolery From Austria, joined Jan 2004, 529 posts, RR: 2
Reply 11, posted (2 years 1 month 4 weeks 1 day 9 hours ago) and read 12663 times:

Didn't the proliferation of the A320 series in the late 80's/early 90's have a role in Boeing's advancement of the 737 fleet? I understand that when the 737NG program was launched in order compete with the performance numbers of the 320 series. At this time, the MD 90 series was freshly launched, and was an improvement to the existing 737s (300/400/500), so there was nothing really on the table except for the MD95.

It is not clear to me if MD had their eye on the advancements of AB, or if they were too focused on Boeing. In either event, I don't know how long MD's commercial business would have lasted beyond the 90's.

There were aspects that became the gold standard within aircraft families like commonality and interchangeability (this was both, flight deck and systems- including airframe). A & B were quite advanced in this respect.

Getting out of commercial, MD had a valuable defense portfolio- F-15, F/A-18, C-17, in addition to a number of missiles and other defense articles. While MD was struggling with defense cuts of the 90's, and recession that drove commercial customers to the cheaper A320s, Boeing took advantage of their weakness, and bought them for cheap.

While I am quite fond of the MD planes, Boeing was looking for cheap buys, and MD, and even Rockwell were snapped up pretty cheap. Getting rid or redundancy is the name of the game, and unfortunately, Boeing's commercial products won out.



Paper makes an airplane fly
User currently offlineBobloblaw From United States of America, joined Jan 2012, 1725 posts, RR: 1
Reply 12, posted (2 years 1 month 4 weeks 1 day 8 hours ago) and read 12374 times:

I dont think the DC-9-30 had a higher CASM than the 737-200. Certainly the 737 was better for cargo or in combi mode. The market in the late 1960s was for a 100 seat aircraft. Making the DC9 have 20% more seats would be pointless in an era where the average load factor was 60 percent. It wasn't what local service carriers wanted. And a shorter fatter DC9 would probably still weigh the same as a thinner longer model. Among second tier carriers the DC9 probably outsold the 737 first gen. The MD-80 certainly sold well versus the 737 Classics of the mid 1980s.

Where MD falls apart is the MD90 isn't much of a competitor to the 737NG even though the MD-90 had a 2-3 year headstart. I think range is the biggest issue versus the 737NG.


User currently offlinelat41 From United States of America, joined Jun 2004, 478 posts, RR: 0
Reply 13, posted (2 years 1 month 4 weeks 1 day 6 hours ago) and read 11733 times:

What accounts for the MD-90's lower service ceiling. I never see them over the mid 30's. Is that where those engines breathe the best or the wing design.

User currently offlineLN-KGL From Norway, joined Sep 1999, 1070 posts, RR: 4
Reply 14, posted (2 years 1 month 4 weeks 1 day 5 hours ago) and read 11013 times:

The service ceiling for the DC-9s (DC-9-10 -> MD90) was always 37,000 feet. This is not engine related, but system related. Boeing 737 started up with a service ceiling of 35,000 feet with -100 and -200, but with 737 Classic the service ceiling rose to 37,000 feet (same level at the DC-9s). With the arrival of the Airbus A320 in 1987-88 a new standard was set with a service ceiling of 39,000 feet. MDC tried to equal this service ceiling and to do this they had to get rid of aft stairs on the MD95 (new pressure bulkhead), and that's why today the B712 don't have this real pre of the old DC-9s. With the 737NG Boeing had to get even better than the A320 and ended up with a service ceiling 2,000 feet higher at 41,000 feet. Later Airbus too raised the service ceiling to 41,000 fet, but only for A319CJ.

User currently offlineSmittyOne From , joined Dec 1969, posts, RR:
Reply 15, posted (2 years 1 month 4 weeks 1 day 5 hours ago) and read 10896 times:

Quoting quickmover (Reply 2):
I love 5 abreast seating.
Less middle seats. What do you like about 3 by 3 seating?

Same here. Sitting toward the front of a Maddog is the best ride you can get for your money IMO!


User currently offlineB727FA From United States of America, joined Jun 2011, 800 posts, RR: 0
Reply 16, posted (2 years 1 month 4 weeks 1 day 4 hours ago) and read 10498 times:

Quoting gigneil (Reply 8):

DL seats 16/144 on both the 737-800 and the MD-90(K)



My comments/opinions are my own and are not to be construed as the opinion(s) of my employer.
User currently offlineCF-CPI From Canada, joined Nov 2000, 1111 posts, RR: 0
Reply 17, posted (2 years 1 month 4 weeks 1 day 4 hours ago) and read 10409 times:

Quoting TomFoolery (Reply 11):
I understand that when the 737NG program was launched in order compete with the performance numbers of the 320 series.

I have heard the same thing. I'm told that the real motivator was UA going to Airbus because the A320 could do DEN-east coast nonstop, something that eluded the 737-400.


User currently offlineoykie From Norway, joined Jan 2006, 2754 posts, RR: 4
Reply 18, posted (2 years 1 month 4 weeks 1 day 3 hours ago) and read 9848 times:

Quoting TrijetsRMissed (Reply 6):

Classic conservative mismanagement, Ala GM circa 2004-07. Unfortunately, Clinton didn't bailout MD and implement and mandatory corp restructure to save the company.

Unfortunately true. It reminds me about the book Car Guys vs. Bean Counters from Bob Lutz. He has told how the company used to be run by engineers and not bean counters.

I believe the very same deal happened to MDC. It was started by an aeronautical engineer that built wonderful airplanes.



Dream no small dream; it lacks magic. Dream large, then go make that dream real - Donald Douglas
User currently offlineb767 From Norway, joined Feb 2008, 127 posts, RR: 0
Reply 19, posted (2 years 1 month 4 weeks 1 day 2 hours ago) and read 9329 times:

How was fuel per seat/mile cost compared to the 737-800 on longer legs?The 737NG had 10 percent more wing area and perhaps a slightly better lift/drag ratio which mean it could cruise at higher altitudes,but then again the 737 had it,s aerodynamic drawbacks with the nose design(perhaps not important since most drag come from wings ,tailplane,engine etc.)When looking at the aircraft data on A.net the range seems similar,so I don,t know if that is the issue.But on the other hand,I have heard the MD90 could not fly US transcontinal non stop. Could the answer why it didnt sell, simply be problems with the electrical system and the IAE in the early days(Delta got mad) and the Boeing MD merger?

User currently offlineMasseyBrown From United States of America, joined Dec 2002, 5562 posts, RR: 7
Reply 20, posted (2 years 1 month 4 weeks 1 day 2 hours ago) and read 9056 times:

Quoting Antoniemey (Reply 3):
Ah, but see, it's not what we like about 3x3, it's what the airlines like.

3x3 narrow bodies were designed to make a LOT of money at 67% load factors. Those middle seat were for surge capacity to accommodate holiday traffic and cancellation rebooks and were not intended to be full routinely.

Time, economics, and unbelievable forbearance by passengers have allowed the airlines to turn them into torture chambers.



I love long German words like 'Freundschaftsbezeigungen'.
User currently offlinePC12Fan From United States of America, joined Jan 2007, 2457 posts, RR: 5
Reply 21, posted (2 years 1 month 4 weeks 1 day 2 hours ago) and read 9035 times:

I don't know what it is about the Mad Dog 90, it's just basically the -80 with bigger engines but it's one of my favorite birds. Would have loved to see have been the majority in the TWA fleet. (just the fantasy guy talking there)

I am curious though of how a blended winglet application would have contributed to the wing. I have a sneaking suspicion that the wing wouldn't have needed to be reinforced very much.  



Just when I think you've said the stupidest thing ever, you keep talkin'!
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 22, posted (2 years 1 month 4 weeks 22 hours ago) and read 7193 times:

Quoting TrijetsRMissed (Reply 10):
For the MD-90, it was timing. Only 2 years after EIS did Boeing acquire MD. And talks originated while the MD-90 was getting certified. It never had a chance.

DL had a lot of problems when the MD-90 was first introduced with them. There were engine and system problems that essentially were not resolved by MDC, and Boeing had no interest in the MD-90. They wanted to sell the B-737NG, not a The MD-90 was initially a reengined MD-88warmed over DC-9. DL ended up cancelling their order after airplane #14. Only about 85 MD-90s were built.

The MD-90 was initially a reengined MD-88, with a higher MTOW, but carrying the same number of pax over the same range.

However DL found ways to fix the airplane on their own and have since been buying every MD-90 they can get their hands on. But DL is only interested in the basic MD-90-30. They have no interest in aquiring the MD-90-30-IGW/-ER/-T versions as there are only one or two versions of these varients each. I believe DL now has about 60 MD-90-30s now.


User currently offlineDeltaMD90 From United States of America, joined Apr 2008, 7972 posts, RR: 51
Reply 23, posted (2 years 1 month 4 weeks 22 hours ago) and read 7183 times:

Quoting KC135TopBoom (Reply 23):
I believe DL now has about 60 MD-90-30s now.

And a bit of random trivia, DL had orders for over 100. It would be a better trivia fact if I could remember the right number but maybe someone can fill me in



Ironically I have never flown a Delta MD-90 :)
User currently offlinedtw9 From United States of America, joined Sep 2003, 1170 posts, RR: 2
Reply 24, posted (2 years 1 month 4 weeks 22 hours ago) and read 7212 times:

Quoting KC135TopBoom (Reply 23):
Only about 85 MD-90s were built.

116 were built

Quoting KC135TopBoom (Reply 23):
They have no interest in aquiring the MD-90-30-IGW/-ER/-T versions as there are only one or two versions of these varients each

Delta has taken IGW/ER's

Quoting KC135TopBoom (Reply 23):
I believe DL now has about 60 MD-90-30s now.

Delta has 65 in service or purchased and are looking for 12 to 15 more

Quoting DeltaMD90 (Reply 24):
And a bit of random trivia, DL had orders for over 100. It would be a better trivia fact if I could remember the right number but maybe someone can fill me in

Delta's original order was for 50 firm and 110 options


User currently offlineViscount724 From Switzerland, joined Oct 2006, 25871 posts, RR: 22
Reply 25, posted (2 years 1 month 4 weeks 20 hours ago) and read 7211 times:

Quoting dtw9 (Reply 25):
Quoting KC135TopBoom (Reply 23):
Only about 85 MD-90s were built.

116 were built

Including 2 built in China.


User currently offlineViscount724 From Switzerland, joined Oct 2006, 25871 posts, RR: 22
Reply 26, posted (2 years 1 month 4 weeks 20 hours ago) and read 7286 times:

Quoting DocLightning (Reply 7):
The big advantage to rear-mounted engines is FOD protection.

However rear-mounted engines are more prone to ingesting ice shed from the wings and fuselage, as SAS discovered at ARN in 1991.


View Large View Medium
Click here for bigger photo!

Photo © Ola Carlsson



A few have also had engines separate due to ice ingestion, including this NW 727-200.


View Large View Medium
Click here for bigger photo!

Photo © Brian Harrison



User currently offline727forever From United States of America, joined Jan 2006, 794 posts, RR: 5
Reply 27, posted (2 years 1 month 4 weeks 18 hours ago) and read 7284 times:

Quoting KC135TopBoom (Reply 23):

The MD-90 was initially a reengined MD-88, with a higher MTOW, but carrying the same number of pax over the same range.

Not exactly. It is longer and in the DL configuration the MD-90 carries 11 pax more. The electrical system is quite different, which was one of the problems early on in the airplanes existance. It has far better brakes than the MD-80. It has a vacuum lavatory system which is much better. The APU is stronger with larger a/c packs to give better cooling. So, not exactly a warmed over MD-88.

Maybe a few answers to FAQ's in this thread. I've been flying the beast for a few years anyway and will answer what I can.

Was the wing too small?

Yes, this is a problem with the MD-90, though I don't think in and of itself was the reason for so few orders being filled. If the airplane is full and it is to fly a 4 hour flight, the initial max altitude will be around 30,000' due to G load/mach buffet. It has the power to go higher, but not enough wing margin. As it burns off fuel it can climb to as high as 33,000'. The thing is with the IAE engines, the MD-90 fully loaded at 33,000' has basically the same fuel burn as a CFM powered A320 at 35,000' or 36,000'.

Was the lack of coast to coast range why it didn't sell well?

I don't think so. It was designed as a 727 replacement which was a 4 hour airplane as well. The MD-90 does the same roll on 45% less fuel burn. From the start of the MD-90 design there was an MD-90-50T to come after the initial MD-90-30. Unfortunately, the MD-90-50T which would have had additional fuel tanks in the belly like the MD-83 and would be capable of coast to coast, was never built as orders dried up.

Was the 2x3 seating the reason it didn't sell well?

2x3 is narrower than the 3x3 which has a lower parasite drag. However, being that the MD-90 has tail mounted engines it must have a longer fuselage ahead of the center of gravity to counter the weight of the engine. To counter this weight, the horizontal stabilizer does more work to balance out the weight which adds more drag. Based on the fact that the MD-90 and A320 have basically the same fuel burn at the same altitude with the same engines, I'd say that it's a wash so no, the 2x3 seating didn't have a negative effect.

Rear mounted engines and ice FOD?

Really? This is a stretch. If crews use proper procedure for anti-ice use, this is again not a factor. I've flown the MD-90 into some of the worse icing I've ever seen. It was so bad we could hear the ice hitting the airplane and had nearly an inch of mixed ice on the nose and forward fuselage. We had no problem with FOD or even the wing hanging in there. While slick on landing, the carbon brakes and very effective and reverse thrust did a good job getting us stopped on a poor runway.

727forever



727forever
User currently offlineakelley728 From United States of America, joined Dec 1999, 2194 posts, RR: 5
Reply 28, posted (2 years 1 month 4 weeks 13 hours ago) and read 6814 times:

Quoting KC135TopBoom (Reply 22):
But DL is only interested in the basic MD-90-30. They have no interest in aquiring the MD-90-30-IGW/-ER/-T versions as there are only one or two versions of these varients each.

Wrong. The T version are the 2 built in China and are both with Delta now. As was stated earlier, they took the ERs/IGWs as well.

The MD-90s that DL is NOT interested in are the ex-Saudia ones due to cockpit differences.


User currently offlineDocLightning From United States of America, joined Nov 2005, 20246 posts, RR: 59
Reply 29, posted (2 years 1 month 4 weeks 12 hours ago) and read 6800 times:

Quoting MasseyBrown (Reply 20):
Time, economics, and unbelievable forbearance by passengers have allowed the airlines to turn them into torture chambers.

Do you know what my solution to this has been? I pay up. Seriously. I pay for advance seat selection. I pay for Y+ if it's reasonable (it usually comes with some perks). Flying isn't quite so miserable that way.


User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 30, posted (2 years 1 month 4 weeks 12 hours ago) and read 6756 times:

Quoting TomFoolery (Reply 11):
There were aspects that became the gold standard within aircraft families like commonality and interchangeability (this was both, flight deck and systems- including airframe). A & B were quite advanced in this respect.

   Agreed, both A & B were better versed in commonality. MDC was headed in that direction. The MD-90 and MD-95 were to each to have a family of three. From 1995, MDC's goal was to have commonality between 6 sub-types in operation by 2000. The MD-90 was also offered with the MD-88-like EFIS, to provide commonality with MD-80 series as well. All but one client chose this option.

Quoting Bobloblaw (Reply 12):
Where MD falls apart is the MD90 isn't much of a competitor to the 737NG even though the MD-90 had a 2-3 year headstart. I think range is the biggest issue versus the 737NG.

I don't have the numbers handy, but the MD-90's fuel tank is significantly smaller than the 737NG. (Much like a 717 vs an A319). The MD90-30ER is more comparable and was offered from the beginning. But at the time airlines didn't feel it was needed. Having a 737 or A320 on near trans-cons was not common in 1995, as it is today.

Quoting KC135TopBoom (Reply 22):
DL had a lot of problems when the MD-90 was first introduced with them. There were engine and system problems that essentially were not resolved by MDC, and Boeing had no interest in the MD-90. They wanted to sell the B-737NG, not a The MD-90 was initially a reengined MD-88warmed over DC-9.

KC135TopBoom, I was there in the spring of 1997 when MDC deployed resources to DFW to shore-up the dispatch reliability issues... And things started to improve, but as I noted earlier, the level of support went into the ground once Boeing's acquisition of MD was complete. Thus, DL's issues were elongated into the early 2000's, largely because TechOps tried to use the MD-88 book, if you will. History shows the DL MD-90 problem was more of a DL problem, than the MD-90. Not unlike AA and the A300.

Quoting KC135TopBoom (Reply 22):
DL ended up cancelling their order after airplane #14.

Incorrect. DL cancelled the MD-90 order in Q4 1997. Once the merger was approved, Boeing sold DL on the 738 and convinced them to cancel the MD-90 order, as production was to be ceased.

Quoting dtw9 (Reply 24):
Delta's original order was for 50 firm and 110 options

   Correct. But the order was revised prior to first delivery. The final order was 31 firm plus 116 options. From 05/97, DL planned to convert 50-70 options, with deliveries into 2003.

Quoting 727forever (Reply 27):
It was designed as a 727 replacement which was a 4 hour airplane as well.

   DL ordered the MD-90 specifically to replace the 727 fleet.



There's nothing quite like a trijet.
User currently offlineXFSUgimpLB41X From United States of America, joined Aug 2000, 4224 posts, RR: 37
Reply 31, posted (2 years 1 month 4 weeks 12 hours ago) and read 6802 times:

An interesting note on the MD-90- at a heavy takeoff weight, it can require up to 265 (ish) knots to retract the slats for manuevering margin. It is one of the few narrowbodies to be able to go above 250 knots below 10,000 feet!


Chicks dig winglets.
User currently offlinePHX787 From Japan, joined Mar 2012, 7859 posts, RR: 19
Reply 32, posted (2 years 1 month 4 weeks 12 hours ago) and read 6720 times:

Quoting quickmover (Reply 2):
I love 5 abreast seating.
Less middle seats. What do you like about 3 by 3 seating?

I made sure I booked a seat on the 2-seat side of the plane on my flight to MSP.

Quoting Antoniemey (Reply 3):
By widening their base fuselage enough to squeeze in a 6th seat per row, Boeing was able to make an aircraft in the same size class as the competing Douglass/MD model that fit 20% more passengers.

Or what about the C-series and E-series, with 2 abreast on each side?

Quoting TrijetsRMissed (Reply 30):
DL ordered the MD-90 specifically to replace the 727 fleet.

Where are they typically based from now?



我思うゆえに我あり。(Jap. 'I think, therefore I am.')
User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 33, posted (2 years 1 month 4 weeks 12 hours ago) and read 6700 times:

Quoting PHX787 (Reply 32):
Where are they typically based from now?

ATL and MSP. ATL has the highest number of daily MD-90 departures, whereas the MD-90 at MSP makes up a higher percentage of the total DL departures. Previous bases included DFW (95-05) and SLC (05-10).



There's nothing quite like a trijet.
User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 34, posted (2 years 1 month 4 weeks 11 hours ago) and read 6659 times:

Quoting dtw9 (Reply 24):
elta has 65 in service or purchased and are looking for 12 to 15 more

Looking to come to an agreement on price and timeline for the next 12-15. The specific frames to be acquired have been determined.



There's nothing quite like a trijet.
User currently offlineKC135TopBoom From United States of America, joined Jan 2005, 12173 posts, RR: 51
Reply 35, posted (2 years 1 month 4 weeks 6 hours ago) and read 6437 times:

Quoting XFSUgimpLB41X (Reply 31):
It is one of the few narrowbodies to be able to go above 250 knots below 10,000 feet!

Actually, no. Most commerical airliners are capable of exceeding 250 knots below 10,000', but the speed restriction is regurlatiory. The first several years I flew the KC-135, initial climb airspeed was 285 knots, but that changed to 250 knots by the FAA in the mid to late 1970s. In that same regulation change, landing lights were also required to be left on until 10,000'. It was thought the lights and slower airspeed would help reduce the possibility of bird strikes. That has since been proven wrong but the 250 knot speed restriction remains, as well as the lighting.

After passing 10,000' the speed restiction goes away and airplanes can climb out at their best performance airspeed.


User currently offlineAlnicocunife From United States of America, joined Mar 2011, 175 posts, RR: 0
Reply 36, posted (2 years 1 month 4 weeks 5 hours ago) and read 6286 times:

[quote=Viscount724,reply=26]However rear-mounted engines are more prone to ingesting ice shed from the wings and fuselage, as SAS discovered at ARN in 1991.

Ice ingestion is NOT an issue with MD-90's The V2500 circulate warm fuel back to the tank. No ice or frost build up from cold soaking, humidity.

MD Never improved anything! MD-88, 90 and B717 are all DC-9's with "modern" cockpits and engines. The MD-90 is a "fly by wire" aircraft but MDC used piano wire. Structurally almost all of the same repairs are in the Structural Repair Manual for all types. Some of the pages still have DC-9 on them. Just adding a repair to the MD-90 manual is not improving the aircraft. Same cracks, same repairs, same location. Delta had great plans for the MD-90 until the first year of service when the dispatch reliability was about 26%. There were so many issues that took YEARS to correct. Now the MD-90 is in the 98% dispatch reliability.

Pros of the MD-90

Both engines running are quieter than the APU. And the ride in the front of the cabin is quiet. On takeoff you cannot hear the engines, you just get pushed into your seat. For Delta they are cheap, fuel efficient and can fly hot and heavy from the western states to MSP


User currently offline727forever From United States of America, joined Jan 2006, 794 posts, RR: 5
Reply 37, posted (2 years 1 month 4 weeks 4 hours ago) and read 6200 times:

Quoting KC135TopBoom (Reply 35):

Actually, no. Most commerical airliners are capable of exceeding 250 knots below 10,000', but the speed restriction is regurlatiory. The first several years I flew the KC-135, initial climb airspeed was 285 knots, but that changed to 250 knots by the FAA in the mid to late 1970s. In that same regulation change, landing lights were also required to be left on until 10,000'. It was thought the lights and slower airspeed would help reduce the possibility of bird strikes. That has since been proven wrong but the 250 knot speed restriction remains, as well as the lighting.

You misunderstood his point. What he was saying is that the MD-90 may exceed 250 knots below 10,000' because at high weights it's minimum clean configuration speed to maintain stall margin is in excess of 250 knots indicated. In fact at 168,000 lbs min clean speed is 272 knots. There are places that the speed limit is not waived due to airspace restrictions such as MDW, HOU, DFW, etc. When this occurs the pilots will leave the slats extended to be able to maneuver at around 210 up to min clean or leave the takeoff flaps extended and fly down to V2+20 if less than 200 knots is needed.

Quoting Alnicocunife (Reply 36):
Ice ingestion is NOT an issue with MD-90's The V2500 circulate warm fuel back to the tank. No ice or frost build up from cold soaking, humidity.

I think he was referencing airframe environmental ice, but I could be wrong. The cold fuel soaked wing issue was a problem in the early days of the MD-80, but that was fixed with the electric heating blankets on the MD-80 and the Fuel Return to Tank System (FRTT) on the MD-90 and B-717. Boeing could have used a system like this on it's widebodies as the polar routes are altitude restricted due to cold fuel issues. FRTT would fix that.

727forever



727forever
User currently offlineB727FA From United States of America, joined Jun 2011, 800 posts, RR: 0
Reply 38, posted (2 years 1 month 4 weeks 1 hour ago) and read 5943 times:

Quoting Viscount724 (Reply 25):
Including 2 built in China.

Point of clarification please. As we know, a statement of the location of final assembly of an a/c must be available for pax. I usually only see this on the safety card. For those two off shore builds (the Chinese ones), shouldn't the safety cards for those planes say, "Final assembly of this aircraft was completed in China." ???



My comments/opinions are my own and are not to be construed as the opinion(s) of my employer.
User currently offlineKingAir200 From United States of America, joined May 2006, 1629 posts, RR: 2
Reply 39, posted (2 years 1 month 4 weeks 1 hour ago) and read 5902 times:

Quoting B727FA (Reply 38):

They do. That's what the black stripe MD-90 cards are for.



Hey Swifty
User currently offlinePHX787 From Japan, joined Mar 2012, 7859 posts, RR: 19
Reply 40, posted (2 years 1 month 4 weeks 1 hour ago) and read 5869 times:

Quoting KingAir200 (Reply 39):
Quoting B727FA (Reply 38):

What's the reg and serial numbers of those two built in China?



我思うゆえに我あり。(Jap. 'I think, therefore I am.')
User currently offlinedtw9 From United States of America, joined Sep 2003, 1170 posts, RR: 2
Reply 41, posted (2 years 1 month 4 weeks ago) and read 5857 times:

Quoting PHX787 (Reply 40):
What's the reg and serial numbers of those two built in China?

N964DN and N965DN. S/N 60001 and 60002 C/N 4001 and 4002


User currently offlineMaverickM11 From United States of America, joined Apr 2000, 17786 posts, RR: 46
Reply 42, posted (2 years 1 month 4 weeks ago) and read 5827 times:

Quoting 727forever (Reply 27):
Was the lack of coast to coast range why it didn't sell well?
Quoting Bobloblaw (Reply 12):
I think range is the biggest issue versus the 737NG.
Quoting TrijetsRMissed (Reply 30):
The MD90-30ER is more comparable and was offered from the beginning. But at the time airlines didn't feel it was needed. Having a 737 or A320 on near trans-cons was not common in 1995, as it is today.

I don't think it was coast-to-coast range that was the issue; I've heard AA was uninterested in the M90 because it couldn't consistently make DFWBOS/SEA, particularly in light of the M11 shortcomings. I think DL was similarly unimpressed--at the time 



E pur si muove -Galileo
User currently offlinejustinlee From China, joined Aug 2012, 331 posts, RR: 0
Reply 43, posted (2 years 1 month 3 weeks 6 days 23 hours ago) and read 5719 times:

Quoting Viscount724 (Reply 25):

Quoting dtw9 (Reply 25):
Quoting KC135TopBoom (Reply 23):
Only about 85 MD-90s were built.

116 were built

Including 2 built in China.

Chinese have built 4 more! Just look at ARJ21  

[Edited 2012-10-01 11:23:10]

User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 44, posted (2 years 1 month 3 weeks 6 days 21 hours ago) and read 5520 times:

Quoting Alnicocunife (Reply 36):
Ice ingestion is NOT an issue with MD-90's The V2500 circulate warm fuel back to the tank. No ice or frost build up from cold soaking, humidity.

MD Never improved anything! MD-88, 90 and B717 are all DC-9's with "modern" cockpits and engines. The MD-90 is a "fly by wire" aircraft but MDC used piano wire. Structurally almost all of the same repairs are in the Structural Repair Manual for all types. Some of the pages still have DC-9 on them. Just adding a repair to the MD-90 manual is not improving the aircraft. Same cracks, same repairs, same location. Delta had great plans for the MD-90 until the first year of service when the dispatch reliability was about 26%.

Alnicounife, pure comedy.   Your first point on ice ingestion proves there were improvements! The FRTT 727forever noted is another example.

As for the piano wire joke, the MD-90 incorporates hydraulics with it's pitch control. The MD-80's control column only moves control tabs on the flight surfaces, giving the aircraft a heavy feel. With hydraulics, the MD-90 controls are more balanced and require less trimming.

Lastly, I know you may have fixed many MD-90s in your day, and how frustrating that was for a new airplane. But if we're going to exaggerate dispatch reliability, or lack thereof, let's at least make it somewhat believable.  



There's nothing quite like a trijet.
User currently offlineB727FA From United States of America, joined Jun 2011, 800 posts, RR: 0
Reply 45, posted (2 years 1 month 3 weeks 6 days 21 hours ago) and read 5442 times:

Quoting KingAir200 (Reply 39):
They do. That's what the black stripe MD-90 cards are for.

Thanks, King. I've only ever seen the yellow (overwater) and the purple. I'll have to keep my eyes peeled!



My comments/opinions are my own and are not to be construed as the opinion(s) of my employer.
User currently offlinemilesrich From United States of America, joined Jul 2003, 2009 posts, RR: 6
Reply 46, posted (2 years 1 month 3 weeks 6 days 16 hours ago) and read 5160 times:

Quoting DocLightning (Reply 7):
Quoting DeltaMD90 (Reply 4):
Was this really why MD lost against the 737? I've read this somewhere before, and it makes sense, but I'm not sure if there were other factors that killed the DC-9 series...

Yes, that is how. The big advantage to rear-mounted engines is FOD protection. When the 727 and DC-9 were being designed, there were still a lot of semi-prepared smaller airports that were in use and FOD was an issue. Also, some of the smaller stations couldn't reach all the way up to a 707 fuselage with their airstairs or unload luggage from a plane that tall, so the DC-9 and 727 were put close to the ground, which meant no under-wing engines (until Boeing figured out how to squeeze them under there on the 737.

But it turns out that 3x3 is more efficient because it gives you 20% more passengers in a plane of the same length for less than 20% extra drag. It also turns out that under-wing engines are the most efficient arrangement. The 737 was just the better design.

I hope this wasn't said before, there were a lot of responses, but the reason the DC-9 first outsold the 737 was earlier delivery dates and no Flight Engineer requirement. The DC-9-30 was available a fully year before the 737-200. But the use of airstairs had nothing to do with it. The Boeing line of aircraft door sills were no higher than that of a DC-4, 6, or 7. The 737 had a built in front airstair.

As far as FOD, Foreign Object Damage, the 737 was certified to operate from gravel runways with certain modifications, even though the engines were much closer to the ground. The T-Tail design was used because until the 737, the T-Tail was thought to create better short field takeoff characteristics. Hence, the Caravelle, the Trident, the 727, the BAC-111, and the DC-9. The cabins, except in the very rear seats next to the engines were also quieter. The 737 Advanced improvement, after the elimination of the 3rd crew member requirement, is what really jumpstarted the 737. While Boeing was improving it's product, McDonnell Douglas, with the emphasis on McDonnell was sitting on its laurels and not investing as much in improving it's design. The DC-9-50 was a stretch of the DC-9-30, and carried more passengers. The MD-80's, 81's, 82's and 83's were all DC-9's. The MD 8- designation was a marketing ploy.
Then Boeing came out with the first "NG" 737, the -500, -300, and -400, all with hi bypass engines. They are called classics but had a different tail assembly and different engines. In the meantime, MD was still depending on low bypass JT-8D's that powered the 737-200's. Look at the airlines that operated the 737 vs the DC-9 and reorders. TW got Series 10 DC-9's, sold them off, then acquired -82's, then acquired Ozark and became a large MD operator, until they shut down. AA acquired neither but bought BAC-111's but then in 1982 started acquiring the MDD product and became the largest user of any DC-9 series aircraft. EA never purchased advanced twins except the 757 before they shut down.

UA didn't buy DC-9's but opted for the 737 operating their DC-6's and Viscounts for another year or two longer than other carriers, waiting for deliveries in early 1968, and then purchased -300, and -500's.

DL was a DC-9 carrier, and MD-88 and MD-90 carrier but acquired a smaller fleet, as I remember 36 frames, 737-232A's in a financing deal where they traded in excess initial delivery L-1011's for leased 737's. Then they bought Western and acquired more 737-200's, the next year in 1987. The original non advanced -247's were soon disposed of, before the last DC-9-32's which were traded in on new MD-88's in 1992 when the 9-32's were 25 years old. They never bought any more new 737's until they bought the NG -800's.

NW never acquired either, until they bought Republic, and never flew any 737's. Braniff I flew BAC-111's for a few years, and never bought any more twins from the factory before their shut down in 1982.

NA never had any twin jets, and Pan Am only acquired 737's third hand. (they had some original UA -222's that came via Air Florida).

AL got some 737-200A's but acquired most of their 737's from PI.

CO had both DC-9's and 737's but it is difficult to really discern what "equipment" decisions they made until after Lorenzo was gone as they acquired most of the aircraft from airline acquisitions. The original DC-9-15's were sold off by Bob Six, and he didn't by any other twins. The 737's came from Peoples Express, DC-9's from NY Air.

NE had DC-9-31's that Delta sold off as they were different than their -32's and at the time, DL believed the 727-232A was the key aircraft to operate.

I believe most of the European carriers that acquired the 737-200 bought Advanced models, other than LH with their -100's, and replaced Caravelles, or British aircraft.


User currently offlineqqflyboy From United States of America, joined Oct 2003, 2296 posts, RR: 13
Reply 47, posted (2 years 1 month 3 weeks 5 days ago) and read 4602 times:

I cant' help but think of these any time I see/think of an MD-90:


View Large View Medium
Click here for bigger photo!

Photo © AirNikon Collection-Pima Air and Space Museum
View Large View Medium
Click here for bigger photo!

Photo © AirNikon Collection-Pima Air and Space Museum




The views expressed are mine alone and do not necessarily reflect my employer’s views.
User currently offlineNorthStarDC4M From Canada, joined Apr 2000, 3056 posts, RR: 36
Reply 48, posted (2 years 1 month 3 weeks 4 days 22 hours ago) and read 4455 times:
AIRLINERS.NET CREW
CHAT OPERATOR

Quoting milesrich (Reply 46):
CO had both DC-9's and 737's but it is difficult to really discern what "equipment" decisions they made until after Lorenzo was gone as they acquired most of the aircraft from airline acquisitions. The original DC-9-15's were sold off by Bob Six, and he didn't by any other twins. The 737's came from Peoples Express, DC-9's from NY Air.

CO has DC-9s from Texas International before NYAirs came in.

Quoting milesrich (Reply 46):
EA never purchased advanced twins except the 757 before they shut down.

If you don't count the A300...
They also depending what sources you believe, possibly had an order for 737-300s near the end of the Lorenzo era. (reasoning I heard for this: order was for NYA originally, diverted to EA as part of Lorenzo taking over EA and being forced to sell NYA's shuttle ops to PA, PA got EA 722s instead of NYA MD-80s or 733s. 733s would of replaced those aircraft, instead EA just retasked 727s to Shuttle and cut flying elsewhere)



Those who would give up Essential Liberty to purchase a little Temporary Safety, deserve neither Liberty nor Safety.
User currently offlineB757forever From United States of America, joined May 2010, 425 posts, RR: 3
Reply 49, posted (2 years 1 month 3 weeks 4 days 18 hours ago) and read 4233 times:

Quoting milesrich (Reply 46):
They never bought any more new 737's until they bought the NG -800's.

DL had an order for 50 737-332 aircraft. The first five were delivered but AFAIK, none were operated. They were sold off and the remaining 45 orders were rolled into the -800NG order.


User currently offlinemilesrich From United States of America, joined Jul 2003, 2009 posts, RR: 6
Reply 50, posted (2 years 1 month 3 weeks 4 days 15 hours ago) and read 4071 times:

Quoting B757forever (Reply 49):
DL had an order for 50 737-332 aircraft. The first five were delivered but AFAIK, none were operated. They were sold off and the remaining 45 orders were rolled into the -800NG order.

- I didn't mention the -332's because they were never operated. I thought only two or three were delivered and the other 2 or 3 were sold before they ever got to Atlanta, sort of like Ozark's two 727-200's.


User currently offlineTrijetsRMissed From United States of America, joined Oct 2006, 2391 posts, RR: 7
Reply 51, posted (2 years 1 month 3 weeks 4 days 14 hours ago) and read 4000 times:

Quoting NorthStarDC4M (Reply 48):
Quoting milesrich (Reply 46):
CO had both DC-9's and 737's but it is difficult to really discern what "equipment" decisions they made until after Lorenzo was gone as they acquired most of the aircraft from airline acquisitions. The original DC-9-15's were sold off by Bob Six, and he didn't by any other twins. The 737's came from Peoples Express, DC-9's from NY Air.

CO has DC-9s from Texas International before NYAirs came in.

CO also ordered MD-82s directly from McDonnell Douglas, with deliveries from circa 1984-87. In addition to many MD-81/82s that were acquired secondhand.



There's nothing quite like a trijet.
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