Hi all,

I've spent a considerable amount of time on Delta's remaining DC-9 family aircraft as of late, and I've been giving them some thought.

First, I wanted to confirm with you all that my understanding of the progression is correct.

- Original DC-9-10, roughly the size of an E-175
- DC-9-30 is longer of course, adds a slightly larger wing and more powerful engines
- DC-9-20 retrofits -30 wing and engines to the -10 for added performance for SAS
- DC-9-40 and -50 have more powerful engines but same empennage and fuel capacity and basically trade capacity for range/performance
- MD-81 and MD-82 get further stretched to about the size of an A320, add a larger wing, new/more powerful engines, higher weights, and 2,000 gallons more fuel, updated systems, etc
- MD-83 gets even more powerful engines, higher weights, another 1,200 gallons of fuel
- MD-87 retrofits MD-80 wing, fuel capacity, and engines onto a fuselage sized between DC-9-40 and DC-9-50; produces something with high capability but fairly high costs for the size/era
- MD-90 stretches to about 737-800 size, with new high-bypass engines and higher weights but MD-80 wing and fuel capacity and minimal system updates; resulting product is cost-competitive with 737-800/A320 on shorter routes but lacks performance
- MD-95/717 is sized between DC-9-30 and DC-9-40; returns to DC-9 wing but adds modern high-bypass engines, fly-by-wire, FADEC, and up-to-date systems
Do I have all this right?

Assuming I do, I want to raise some what-ifs:
- I've read of a proposed MD-90-50, with MTOW raised from 166,000 to 173,000 lb, engines powered up from 25,000 to 28,000 lb, and a resulting range increase to 3,500 statute miles
- Such an aircraft would, best I can tell, match the capabilities of the 737-800 and the A320
- I've also read on A.net that McDD had to keep raising engine thrust to make up for their inability to finance a new wing for the MD-90; going all the way to 28,000 lb would seem to validate that

- It seems like what McDD was going for was a two-track program, the MD-95 for short-range routes DC-9s had always flown and the MD-90 to move into the territory 737NGs and A320s now inhabit
- the MD-95 was stymied by the lack of a size family, but McDD planned DC-9-10 and DC-9-50 sized variants
- the MD-90 was stymied by its lack of performance, and didn't get the systems upgrades the MD-95 did; plans to develop an MD-87-style smaller variant were also dropped

So, if we assume for a moment we had a well-capitalized, well-managed McDonnell Douglas in the 90s, could we have seen something like this?
- MD-95 family at 75, 100, and 125 seats, with the BR715 and DC-9 wing/fuel capacity, designed for the role of Delta's 717s/MD-80s/MD-90s, jetBlue's E-190s, etc
- MD-90 family at 125 and 150 seats, with the V2500 and the modern systems of the MD-95, sufficient thrust, weight, and fuel to match the A320/737NG

- Could the MD-90 achieve this using the MD-80's wing or would it need a new one a la 737NG?
- Presumably the MD-95-10 (let's call it) would struggle with scope, but could that family have otherwise won a lot of the E-Jet role?
- Could these aircraft have been successful, and could we be looking at the next generation with geared turbofans and so on coming down the line now? It seems to me the DC-9 isn't any less suited to being modernized than the 737 (probably more) and the long-standing benefits of extremely long cycle life, fewer middle seats, and a quiet first class would endure. Maybe they'd even fix the overhead bin issue with some SpaceBin-style sorcery.

Thoughts? All comments appreciated.

I think, that there is another thread about this topic with many information regarding of speculative "what if's".

BTW, there were also plans for an MD-90EC for European operators, namely Swissair and to a lesser extent for SAS and Finnair.

The 717 is certainly NOT Fly by Wire. Yikes... no.

Otherwise, had MD gone it alone (rather than buying Boeing with Boeing's money), I think we'd have seen some family development.
But the MD-90 HAD to have a better wing, or it was all moot. Bigger engines are great for climbing, but if the wing can't hold the plane up at that altitude, there's little point.
Boeing did toss around a 717-300 after the merger, and even generated some CGI "photos" of it, supposedly for American Airlines.
But it went nowhere.
AA also, supposedly, looked into slapping a variant of the BR715 series onto their MD-80 fleet as a retrofit. That project also, sadly, went nowhere.

All could have been possible if the MD-11 was a hit.

MD80 wrote:

I think, that there is another thread about this topic with many information regarding of speculative "what if's".

BTW, there were also plans for an MD-90EC for European operators, namely Swissair and to a lesser extent for SAS and Finnair.

What did the MD-90EC entail?

All the things we could have potentially seen...

AA737-823 wrote:

The 717 is certainly NOT Fly by Wire. Yikes... no..

Yup, good catch. It's just the spoilers, right?

AA737-823 wrote:

But the MD-90 HAD to have a better wing, or it was all moot. Bigger engines are great for climbing, but if the wing can't hold the plane up at that altitude, there's little point.

This is going to be a hypothetical upon a hypothetical, but does the -90 need more wing than the -80s to carry the extra length or would it be necessary for an -80-size aircraft trying to achieve transcontinental range?

AA737-823 wrote:

AA also, supposedly, looked into slapping a variant of the BR715 series onto their MD-80 fleet as a retrofit. That project also, sadly, went nowhere.

This reminds me, what was that aero upgrade Delta was considering for the Mad Dogs a few years ago?

rlwynn wrote:

All could have been possible if the MD-11 was a hit.

Is it fair to say the MD-11 is the plane that ate Long Beach? I'm genuinely asking, not countering. I know the MD-11s inadequacies are pretty well known, and it should come as no surprise my wide body trijet allegiances lie elsewhere, but I also see MD-80 deliveries plummeted from 140 each in 1990 and 1991 to just 23 by 1994.

There was also the MD-80 UDF, powered by a "propfan." There was a demo aircraft that visited a few airshows, but the project was canned after no airlines ordered it.

MDC and CTAIC came up with an agreement to build the MD-82 and MD-90 in the PRC called the "Trunkliner." These frames were to be 75% built in the PRC for Chinese airlines. There were some legal issues over exporting the tools to build the aircraft, with the U.S. citing that they could be used for other purposes. The parts sat in storage for a period in the 90s, producing only two MD-90s which were NTU by Shenzhen Airlines. IIRC, these frames ended up with Delta.

Postscript to those "other purposes" the U.S. was concerned about.... they were used to develop the ARJ-21

L.1011 wrote:

Hi all,

I've spent a considerable amount of time on Delta's remaining DC-9 family aircraft as of late, and I've been giving them some thought.

First, I wanted to confirm with you all that my understanding of the progression is correct.

- Original DC-9-10, roughly the size of an E-175
- DC-9-30 is longer of course, adds a slightly larger wing and more powerful engines
- DC-9-20 retrofits -30 wing and engines to the -10 for added performance for SAS
- DC-9-40 and -50 have more powerful engines but same empennage and fuel capacity and basically trade capacity for range/performance
- MD-81 and MD-82 get further stretched to about the size of an A320, add a larger wing, new/more powerful engines, higher weights, and 2,000 gallons more fuel, updated systems, etc
- MD-83 gets even more powerful engines, higher weights, another 1,200 gallons of fuel
- MD-87 retrofits MD-80 wing, fuel capacity, and engines onto a fuselage sized between DC-9-40 and DC-9-50; produces something with high capability but fairly high costs for the size/era
- MD-90 stretches to about 737-800 size, with new high-bypass engines and higher weights but MD-80 wing and fuel capacity and minimal system updates; resulting product is cost-competitive with 737-800/A320 on shorter routes but lacks performance
- MD-95/717 is sized between DC-9-30 and DC-9-40; returns to DC-9 wing but adds modern high-bypass engines, fly-by-wire, FADEC, and up-to-date systems
Do I have all this right?

Assuming I do, I want to raise some what-ifs:
- I've read of a proposed MD-90-50, with MTOW raised from 166,000 to 173,000 lb, engines powered up from 25,000 to 28,000 lb, and a resulting range increase to 3,500 statute miles
- Such an aircraft would, best I can tell, match the capabilities of the 737-800 and the A320
- I've also read on A.net that McDD had to keep raising engine thrust to make up for their inability to finance a new wing for the MD-90; going all the way to 28,000 lb would seem to validate that

- It seems like what McDD was going for was a two-track program, the MD-95 for short-range routes DC-9s had always flown and the MD-90 to move into the territory 737NGs and A320s now inhabit
- the MD-95 was stymied by the lack of a size family, but McDD planned DC-9-10 and DC-9-50 sized variants
- the MD-90 was stymied by its lack of performance, and didn't get the systems upgrades the MD-95 did; plans to develop an MD-87-style smaller variant were also dropped

So, if we assume for a moment we had a well-capitalized, well-managed McDonnell Douglas in the 90s, could we have seen something like this?
- MD-95 family at 75, 100, and 125 seats, with the BR715 and DC-9 wing/fuel capacity, designed for the role of Delta's 717s/MD-80s/MD-90s, jetBlue's E-190s, etc
- MD-90 family at 125 and 150 seats, with the V2500 and the modern systems of the MD-95, sufficient thrust, weight, and fuel to match the A320/737NG

- Could the MD-90 achieve this using the MD-80's wing or would it need a new one a la 737NG?
- Presumably the MD-95-10 (let's call it) would struggle with scope, but could that family have otherwise won a lot of the E-Jet role?
- Could these aircraft have been successful, and could we be looking at the next generation with geared turbofans and so on coming down the line now? It seems to me the DC-9 isn't any less suited to being modernized than the 737 (probably more) and the long-standing benefits of extremely long cycle life, fewer middle seats, and a quiet first class would endure. Maybe they'd even fix the overhead bin issue with some SpaceBin-style sorcery.

Thoughts? All comments appreciated.

Well, you missed the MD-88. Semi glass cockpit MD-82. Massively improved over the 80/81/82/83.

VSMUT wrote:

MD80 wrote:

I think, that there is another thread about this topic with many information regarding of speculative "what if's".

BTW, there were also plans for an MD-90EC for European operators, namely Swissair and to a lesser extent for SAS and Finnair.

What did the MD-90EC entail?

"EC" stood for European Community and later for "Enhanced Configuration". McDonnell Douglas offered several of their MD-90-variants as "EC" with weights etc. more adapted to European demands. This also included even more stretched MD-90s for 180 passengers in 2 classes and well over 200 in all-tourist. Swissair, Austrian Airlines, SAS, and Finnair were believed to be the main "target". SAS already ordered the MD90-30. After Swissair and Austrian decided to go for the Airbus A320/321, the MD-90EC was no longer "European Community", but "Enhanced Configuration".

Regards

As mentioned, the MD-88 flew after the MD-87 and before the MD-90. It was the same size as the MD-81/82/83, but with an upgraded cockpit and other small changes.

Strangely enough, McDonnell Douglas offered a different MD-88 in early 1984, which specified a 57-inch stretch and V2500 engines. The proposal seems virtually identical to the MD-90, which got its launch order from Delta in late 1989. In the mid-1980s, Douglas also proposed an 173-seat MD-89 and 180-seat MD-90X, both powered by the V2500. This was before it failed in trying to sell the propfan-engined MD-91 and MD-92, and resorted to the MD-90.

If Douglas had launched the original MD-88 in 1984, they probably would have had that version of the MD-88 flown and in service by the time they eventually launched the MD-90. Considering that the peak of the airline ordering cycle was sometime in 1989 (I think), would McDonnell Douglas have reaped major benefits and been able/willing to stay independent longer? Would they have been able to gain traction with the MD-89, MD-90X, or other V2500-powered derivatives as follow-ups? Would Douglas have significantly slowed the acceptance of the A320?

Without the benefit of hindsight, I think Douglas made the right call to go for the MD-91/92, since with the same V2500 engines (or any identical engine) the A320 would always beat a DC-9 derivative performance-wise due to the A320's preferable wing-mounted engine configuration. An early decision to go with the V2500 might've worked out better in the short- to medium-term, though.

L.1011 wrote:

So, if we assume for a moment we had a well-capitalized, well-managed McDonnell Douglas in the 90s, could we have seen something like this?
- MD-95 family at 75, 100, and 125 seats, with the BR715 and DC-9 wing/fuel capacity, designed for the role of Delta's 717s/MD-80s/MD-90s, jetBlue's E-190s, etc
- MD-90 family at 125 and 150 seats, with the V2500 and the modern systems of the MD-95, sufficient thrust, weight, and fuel to match the A320/737NG

- Could the MD-90 achieve this using the MD-80's wing or would it need a new one a la 737NG?
- Presumably the MD-95-10 (let's call it) would struggle with scope, but could that family have otherwise won a lot of the E-Jet role?
- Could these aircraft have been successful, and could we be looking at the next generation with geared turbofans and so on coming down the line now? It seems to me the DC-9 isn't any less suited to being modernized than the 737 (probably more) and the long-standing benefits of extremely long cycle life, fewer middle seats, and a quiet first class would endure. Maybe they'd even fix the overhead bin issue with some SpaceBin-style sorcery.

Thoughts? All comments appreciated.

Definitely a new wing would've helped. I don't know how the MD-95 would've done; its success probably would've depended on the health of the MD-90 family, for commonality purposes, and because the 150-seat category became dominant. I don't think the geared turbofans would've helped the MD-9x that much, since again the A320 could also mount it, and the B737's LEAP engine is still competitive. Douglas needed a superior engine for its DC-9 variants that couldn't be used on the A320 and B737 to really thrive. But maybe it could still survive with the GTFs.

reltney wrote:

Well, you missed the MD-88. Semi glass cockpit MD-82. Massively improved over the 80/81/82/83.

CowAnon wrote:

As mentioned, the MD-88 flew after the MD-87 and before the MD-90. It was the same size as the MD-81/82/83, but with an upgraded cockpit and other small changes.

Right! Now, am I correct in thinking that the MD-88 cockpit was the same as the basic MD-90 cockpit, and the Advanced Common Flightdeck that I think only Saudia got was a further enhancement which matched the MD-11 and MD-95/717?

CowAnon wrote:

Definitely a new wing would've helped. I don't know how the MD-95 would've done; its success probably would've depended on the health of the MD-90 family, for commonality purposes, and because the 150-seat category became dominant. I don't think the geared turbofans would've helped the MD-9x that much, since again the A320 could also mount it, and the B737's LEAP engine is still competitive. Douglas needed a superior engine for its DC-9 variants that couldn't be used on the A320 and B737 to really thrive. But maybe it could still survive with the GTFs.

There's some element of trade-off between engine configurations though, isn't there? If nothing else, McDD would not be struggling with the ground-clearance related issues that have forced Boeing to Frankenstein the 737 with now infamous consequences. Right?

L.1011 wrote:

There's some element of trade-off between engine configurations though, isn't there? If nothing else, McDD would not be struggling with the ground-clearance related issues that have forced Boeing to Frankenstein the 737 with now infamous consequences. Right?

No. McDD would be struggling with their own massive compromises - engine weight/CoG, for starters; McDD was just as prone to Frankenstein solutions in their own regard. There are posters on a.net (here in the this thread?) who often promote the notion that McDD's leadership and engineering culture took over Boeing in the buyout and not the other way around. Make of that what you will, with regard to 737.

FlyHappy wrote:

No. McDD would be struggling with their own massive compromises - engine weight/CoG, for starters; McDD was just as prone to Frankenstein solutions in their own regard.

Is it fair to say that the minor stretch the -90 got over the -80 was just for center of gravity?

No, it still needed ballast installed

FlyHappy wrote:

L.1011 wrote:

There's some element of trade-off between engine configurations though, isn't there? If nothing else, McDD would not be struggling with the ground-clearance related issues that have forced Boeing to Frankenstein the 737 with now infamous consequences. Right?

No. McDD would be struggling with their own massive compromises - engine weight/CoG, for starters; McDD was just as prone to Frankenstein solutions in their own regard. There are posters on a.net (here in the this thread?) who often promote the notion that McDD's leadership and engineering culture took over Boeing in the buyout and not the other way around. Make of that what you will, with regard to 737.

Faulting McDD for Boeing’s 737MAX debacle 22 years after the merger is a long way to go, to say the least. And certainly dubious. What is indisputable is that the 737 (all variants) had four terrible crashes directly attributed to design flaws (which required redesign) and the DC9/MD80/95/717 had none.

L.1011 wrote:

Hi all,

I've spent a considerable amount of time on Delta's remaining DC-9 family aircraft as of late, and I've been giving them some thought.

First, I wanted to confirm with you all that my understanding of the progression is correct.

- Original DC-9-10, roughly the size of an E-175
- DC-9-30 is longer of course, adds a slightly larger wing and more powerful engines
- DC-9-20 retrofits -30 wing and engines to the -10 for added performance for SAS
- DC-9-40 and -50 have more powerful engines but same empennage and fuel capacity and basically trade capacity for range/performance
- MD-81 and MD-82 get further stretched to about the size of an A320, add a larger wing, new/more powerful engines, higher weights, and 2,000 gallons more fuel, updated systems, etc
- MD-83 gets even more powerful engines, higher weights, another 1,200 gallons of fuel
- MD-87 retrofits MD-80 wing, fuel capacity, and engines onto a fuselage sized between DC-9-40 and DC-9-50; produces something with high capability but fairly high costs for the size/era
- MD-90 stretches to about 737-800 size, with new high-bypass engines and higher weights but MD-80 wing and fuel capacity and minimal system updates; resulting product is cost-competitive with 737-800/A320 on shorter routes but lacks performance
- MD-95/717 is sized between DC-9-30 and DC-9-40; returns to DC-9 wing but adds modern high-bypass engines, fly-by-wire, FADEC, and up-to-date systems
Do I have all this right?

Assuming I do, I want to raise some what-ifs:
- I've read of a proposed MD-90-50, with MTOW raised from 166,000 to 173,000 lb, engines powered up from 25,000 to 28,000 lb, and a resulting range increase to 3,500 statute miles
- Such an aircraft would, best I can tell, match the capabilities of the 737-800 and the A320
- I've also read on A.net that McDD had to keep raising engine thrust to make up for their inability to finance a new wing for the MD-90; going all the way to 28,000 lb would seem to validate that

- It seems like what McDD was going for was a two-track program, the MD-95 for short-range routes DC-9s had always flown and the MD-90 to move into the territory 737NGs and A320s now inhabit
- the MD-95 was stymied by the lack of a size family, but McDD planned DC-9-10 and DC-9-50 sized variants
- the MD-90 was stymied by its lack of performance, and didn't get the systems upgrades the MD-95 did; plans to develop an MD-87-style smaller variant were also dropped

So, if we assume for a moment we had a well-capitalized, well-managed McDonnell Douglas in the 90s, could we have seen something like this?
- MD-95 family at 75, 100, and 125 seats, with the BR715 and DC-9 wing/fuel capacity, designed for the role of Delta's 717s/MD-80s/MD-90s, jetBlue's E-190s, etc
- MD-90 family at 125 and 150 seats, with the V2500 and the modern systems of the MD-95, sufficient thrust, weight, and fuel to match the A320/737NG

- Could the MD-90 achieve this using the MD-80's wing or would it need a new one a la 737NG?
- Presumably the MD-95-10 (let's call it) would struggle with scope, but could that family have otherwise won a lot of the E-Jet role?
- Could these aircraft have been successful, and could we be looking at the next generation with geared turbofans and so on coming down the line now? It seems to me the DC-9 isn't any less suited to being modernized than the 737 (probably more) and the long-standing benefits of extremely long cycle life, fewer middle seats, and a quiet first class would endure. Maybe they'd even fix the overhead bin issue with some SpaceBin-style sorcery.

Thoughts? All comments appreciated.

What an interesting idea for thread! Thank you for your contribution!

I would add that the MD90 also has FADEC, IIRC. And other major system improvements, including brakes, electrical, and hydraulics.

One thing to also consider, is that the MD90 was quite a hit with airlines in Asia. Assuming McDD, could have stemmed the tide, they would have been well positioned for some large upsell orders from these emerging markets in the 2000s.

DeltaMD95 wrote:

FlyHappy wrote:

L.1011 wrote:

There's some element of trade-off between engine configurations though, isn't there? If nothing else, McDD would not be struggling with the ground-clearance related issues that have forced Boeing to Frankenstein the 737 with now infamous consequences. Right?

No. McDD would be struggling with their own massive compromises - engine weight/CoG, for starters; McDD was just as prone to Frankenstein solutions in their own regard. There are posters on a.net (here in the this thread?) who often promote the notion that McDD's leadership and engineering culture took over Boeing in the buyout and not the other way around. Make of that what you will, with regard to 737.

Faulting McDD for Boeing’s 737MAX debacle 22 years after the merger is a long way to go, to say the least. And certainly dubious. What is indisputable is that the 737 (all variants) had four terrible crashes directly attributed to design flaws (which required redesign) and the DC9/MD80/95/717 had none.

You seem to read too much into my words.
It's undeniable that from the 70's and beyond, McDD was fiscally hamstrung, and their design budgets seemed to reflect that, which is why they ultimately were absorbed by Boeing.

Having said that, as solid a safety record as their T-tail family had, the same cannot be said of their trijets.

L.1011 wrote:

Hi all,

I've spent a considerable amount of time on Delta's remaining DC-9 family aircraft as of late, and I've been giving them some thought.

First, I wanted to confirm with you all that my understanding of the progression is correct.

- DC-9-40 and -50 have more powerful engines but same empennage and fuel capacity and basically trade capacity for range/performance

Do I have all this right?

The -40 was only one I missed flying on,

Compared with the DC-9-30, the DC-9-40 is 1.88m (6ft 2in) longer, raising seating capacity in a single class configuration to 125. Apart from the fuselage stretch and more powerful engine options, the -40 was the much the same as the -30.the DC-9-50 is a further 2.44m (8ft 0in) longer than the DC-9-40, or 4.34m (14ft 3in) longer than the DC-9-30.

Source:https://www.airliners.net/aircraft-data/mcdonnell-douglas-dc-9-4050/277