Hawaii50
Topic Author
Posts: 7
Joined: Fri Mar 19, 2004 5:08 am

DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 5:18 am

I have read a lot of posts lately stating that the DC-10-40 was a dog when compared to the -30. What is the reason for this? Also, what are the main differences between the two, besides P&W engines vs. GE.

I have flown on NW DC-10-40's well over a hundred times over the last 30 years, up until they retired them a couple of years ago, and can't recall any blaring delays due to mechanicals so my experience on them was always very positive. I sure do miss the distinctive growl the P&W engines made that the GE powered -30's don't.

Thanks.
Josh
 
flyabr
Posts: 754
Joined: Fri Sep 19, 2003 11:42 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 5:59 am

which one of the engines on the dc-10 sounds like a buzz saw from the front? i believe it's the GE engine but not sure...always thought that sounded odd ...
 
Guest

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 6:12 am

Airlines that specified the DC-10s with JT9 were NWA and JAL only...
The reason, was that their 747s had JT9 engines as well.
They only wish to order DC-10 with common engines (think > spare sparts).
xxx
As a pilot I prefer the CF6. I do not give a damned about the way one or the other sound.
The CF6 is a much more "fine engine" to handle...
JT9s are great for maintenance, you can "tweak" the FCU of a JT9 with hammer and chisel...
Not so with the CF6... it requires very tender loving maintenance care.
xxx
Most of DC-10 sales were with CF6, not JT9.
Both were offered at the same time.
The DC10-10 and 30 were offered with CF6.
The DC10-20 and 40 were offered with JT9. No DC10-20 were ever sold.
xxx
Happy contrails  Smile
(s) Skipper



[Edited 2004-03-18 22:24:16]
 
Guest

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 6:12 am

The 40 has a flared no2 engine like the MD-11


View Large View Medium
Click here for bigger photo!

Photo © Pereslavtsev Alex

 
dutchjet
Posts: 7714
Joined: Sat Oct 14, 2000 6:13 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 6:15 am

A DC-10-20 was never offered or built......actually, the dc-10-20 was renamed the DC-10-40 at the request of NW in order to sound more advanced.

There were also several DC-10-15s built, specially for AeroMex and Mexicana, with improved performance features which helped operations out of hot and high Mexico City.
 
User avatar
yyz717
Posts: 15689
Joined: Mon Sep 10, 2001 12:26 pm

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 6:38 am

The NW and JAL DC-10-40's had different engines. NW JT9D-20, JAL JT9D-59A with different nacelles.

Not sure whether the later -59A for JAL had better performance than the -20A for NW. I imagine it did.

I dumped at the gybe mark in strong winds when I looked up at a Porter Q400 on finals. Can't stop spotting.
 
Hawaii50
Topic Author
Posts: 7
Joined: Fri Mar 19, 2004 5:08 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 6:53 am

I know the sound an engine makes really has no bearing on it's performance, but damn the P&W's sounded cool. The GE's just don't have the same effect.

Why do people believe the 30 is a better A/C over the 40? NW must have thought otherwise initially since they wanted the 20 renumbered to the 40 to show it was an improvement.

 
AR385
Posts: 6742
Joined: Fri Nov 07, 2003 8:25 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 8:02 am

Dutchjet,

Only 7 DC-10-15's were built. Five for MX and two for AM. Most are now on the scrapyard. Before, they were sold to SunCountry and a charter airline in Brasil.
The DC-10-15 was ideal for hot and high climates and that's why it was ordered for MX), Mexico">MEX. It is basically a DC-10-10, but instead of the GE having 52,000 lbs of thrust the '15 had 56,000 or so I believe.

The thing was that since they were built for MX), Mexico">MEX, when you took off at sea level, and the plane was not too heavy, the thing went like a rocket, and the angle of attack during the climb was impressive. Being in the plane was like being in a roller-coaster when it's climbing before the downward ride. One of my all time favorite plane.

Regards
 
Spoon04
Posts: 179
Joined: Tue Mar 09, 2004 11:15 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 12:18 pm

My best friend is a NW DC-10 Captain, and he has informed me numerous times what an absolute P-I-G the -40 was... Lousy climb-rate, draconian avionics and the equally-draconian procedure of having to VERY CAREFULLY retard the Number 2 throttle back prior to general decent. The -40's were purchased under the "tightwad eyes" of Donald Nyrop, and NW basically received what it paid for the aircraft - a "Bargain Basement" version of the DC-10. As mentioned above, the designator "Dash 40" was designed to deceive the general public in thinking that NW's version was the most advanced (As compared to the -10's and -30's) when in fact, the -40's were quite inefficient and a real pain to fly compared to the ex-Swiss Air -30's (akin to transitioning from a Chevrolet Biscayne to a Cadillac).
 
Hawaii50
Topic Author
Posts: 7
Joined: Fri Mar 19, 2004 5:08 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 1:01 pm

What purpose is retarding just the #2 throttle before descent?
 
Guest

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 1:06 pm

Spoon04,

I think that's a common myth-misconception. NW wanted an intercontinental-ranged DC-10, but they demanded PW-engines (their then-CEO made the comment ‘if I want aircraft engines, I’ll buy from PW; if I want a light bulb, I’ll buy from GE.) Unfortunately, their JT9D-20-powered DC-10 proved unreliable; the JT9D-20J were only marginally better.

It’s remarkable that all but one lasted within NW’s fleet for nearly 30 years! (*NW sold three aircraft to Boeing; one was w/o while operating for TZ, the other two were re-acquired several years later.)
 
AR385
Posts: 6742
Joined: Fri Nov 07, 2003 8:25 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 2:31 pm

I think the issue is not retarding number 2 prior to descent. When I flew the DC-10-15 on the simulator, when landing, the instructor told me to set reverse thrust on 1 and 3 before doing it on 2. I really never undertood why. Anybody who knows can explain?, thanks
 
Spoon04
Posts: 179
Joined: Tue Mar 09, 2004 11:15 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 3:10 pm

Hawaii50 and AR385, I'll contact my bud tomorrow tomorrow and get the skinny on the powering-back of the throttle re the -40. It was a very bizarre procedure and I'll be able to provide the details after I talk to him. Stay tuned. It would be great if a forum reader who had experience with the -40 could jump in.
 
AR385
Posts: 6742
Joined: Fri Nov 07, 2003 8:25 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 3:23 pm

Thanks, Spoon04 you are very kind
 
redtailmsp
Posts: 199
Joined: Thu Feb 12, 2004 1:05 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 3:52 pm

Due to the shape of the air intake on the number 2 engine - the "coke-bottle" shape, the DC10-40 was prone to compressor stalls at start of descent under certain wind conditions - so crews had to very carefully manage the retarding of the number 2 engine. This was a phenomena with the Pratt & Whitney JT9D engines and was not an issue with the MD11, which has the same shaped air intake.
The DC10-40 really was a poor performer compared to the -30. NWA bought Pratt engines for commonality with the 747-100s/200s, which Nyrop saw as a sensible solution due to the cost savings. This worked fine as long as the aircraft was operated domestically. They bought the aircraft from Douglas with certified take-off weights which were totally impractical for international operation. From memory, the certified max take-off weight was 498.0 for the DC10-40 with -20 engines and 515.0 for the -20J engines. The -20J engines used water-injection to get more power. The -20 power aircraft could get a 515.5 take-off weight ONLY if the temperature was 68 degrees or less, otherwise, it was 498.0 The result was that even BOS-Europe flights were marginal at best, especially in the summer months. You can imagine the problems we had when the only aircraft available were -20 power.

NWA then decided in the 1992-3 time frame (and at great expense) to get the fleet recertified at a higher take-off weight after countless years of offloading freight (and sometimes passengers too), and the -20J power aircraft were eventually recertified at 530.0 take-off weight. This made things easier - but still MSP-AMS/LGW flights with the -40 were often bumping payload. Incidentally, I think that Japan Airlines had their DC10-40's certified at a take-off weight of 548.0

If Nyrop had bought the aircraft with a higher max take-off weight from the start, this would have allowed the aircraft to be used internationally - but bottom line was that they did not want to spend the money upfront. So, the end result was a domestic airplane that was totally marginal in the international arena. It had higher fuel consumption by far than the -30, it had far lower take-off performance, it had numerous other restrictions that affected its operation internationally. In short, yes, it was a real dog. When we moved to the DC10-30, suddenly we had a REAL airplane to work with internationally. We could carry all the payload we wanted and had very very few restrictions. About the only operations that really restricted its performance were SEA-KIX and SFO-NRT.
 
Guest

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 4:14 pm

I hate to contradict you, but the DC-10-40 was purchased with the intentions of transpacific service – in fact, NW didn’t have much of a domestic network at the time, and the aircraft were deployed into the Pacific shortly after their delivery. ORD-NRT is among the routes that NW has deployed the DC-10-40 on.

The ex-Swiss DC-10-30 were a solution to NW’s then-immediate widebody equipment shortage. The transaction (eight a/c leased for nine years) is cited among Checchi & Friend’s poor decisions that worsened NW’s declining health (the controlling interest in HA for mainly SYD, the $15 million paid for HP’s NRT-NGO route, etc. were among others)… many saw the long-term leases unnecessary as NW had 40 A330/A340 and 6 B744 on order (in addition to 21 DC10-40, 12 B741, 20 B742 – all but five were only four-to-ten-years-old and 10 B744)…
 
TokyoNarita
Posts: 556
Joined: Fri Aug 15, 2003 5:30 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 5:12 pm

There was a detailed article recently in a Japanese aviation book regarding JALs DC-10-40s retirement (which is taking place this year after over 25 years of reliable service) that JAL was pretty much happy with their DC-10-40s overall performance.

When JAL received the first few DC-10-40s, they launched NRT-ANC-JFK in 1977. Historically over the years, about half of their fleet were configured internationally for Japan-Hawaii and Japan-Asia routes. Also, during the 70s and the 80s when JAL had a large operation in the Middle East/India, their DC-10-40s were dominantly used (usually stopped in BKK) over their B747s. The rest of JALs DC-10-40s remained within Japan and operated without the center main gear so the performance issue mentioned in the previous post may not have been a big issue for JAL.

NW owns two ex-JAS (Japan Air System) DC-10-30s. I believe these are some of the last DC-10s ever built (built in the mid 80s). I bet they are a real performer compared to NWs original DC-10-40s. They used to do charters such as NRT-YVR full load without a problem.

TokyoNarita.

 
TokyoNarita
Posts: 556
Joined: Fri Aug 15, 2003 5:30 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 5:18 pm

ORD-NRT is among the routes that NW has deployed the DC-10-40 on

Which stopped in ANC or SEA...didnt it?

TokyoNarita

 
dutchjet
Posts: 7714
Joined: Sat Oct 14, 2000 6:13 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 6:44 pm

I dont want to disagree, but I remember that NW specifically bought the DC10-40 for domestic and Hawaiian operations and the 747s were to be the airlines intercontinental airliner. The DC-10-40 (like the DC-10-10 and L1011-1) were domestic birds, purchased during the late 60s when airlines really thought that they could fill up 250 seat planes on short routes like PHL-DTW and BOS-FLL.......NW went with the DC-10-40, and they showed up on routes throughout their then limited domestic system (even Seattle-Spokane had 2 DC10 flights per day!) NW was not alone, DL and EA purchased a huge number of 1011s and AA and UA for example had large DC10 fleets specifically for domestic service.
 
redtailmsp
Posts: 199
Joined: Thu Feb 12, 2004 1:05 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 11:32 pm

Yes, the DC10-40 did operate ORD-ANC-NRT for a while as a stopgap, and perhaps SEA-ANC-NRT too, but this was all it was, a stopgap. The aircraft was very performance limited between ANC-NRT, so basically it was pax/bags only and often with a seat block - and that was in the days with the original certified operating weight - so it was pax/bags and fumes. As TokyoNarita says, the JAL DC10-40s could operate to HNL easily whereas it would have been a nightmare for NWA. Indeed, I remember one time we did operate a DC10-40 from HNL to Japan in the mid 90's because there was absolutely no other choice - again seat block and fumes operation. And yes, some of those former Thai / JAS aircraft were some of the very last aircraft off the production line - and with a certified max take-off weight of 580.0, they were a dream to dispatch (and still are). Compare that weight to the original weights of the NWA DC10-40 at 498.0 - thats 82.0 greater weight, along with far better fuel consumption. It was like day and night in the operation of the DC10 at Northwest.

The 747 was seen as the international aircraft in the 70s and operated practically all international sectors, including all of the developing Europe and Hawii markets initially. Then with the 747 proving too large for Europe, they began the DC10-40 operation because they had no other aircraft. This was when they operated to several destinations out of BOS - CDG/FRA/LGW/PIK(and later GLA)/AMS in the mid-late 80's. And it was then and only then that they seriously looked at increasing the weights on the -40 - and again as a stopgap - in order to be able to operate on a level playing field with everyone else transatlantic. The DC10-30 was becoming available with the likes of Swissair taking them out of service to be replaced by MD11s and the like - so they were available at the right time for NWA as a quick and cost effective way to dramatically improve their transatlantic operation. I can't talk for the financial aspects of this decision with regard to lease payments, etc, but operationally, it was a very, very smart thing to do. It allowed us to operate current routes that were marginal at best with the -40 to the fullest of their capability - and it allowed us to develop routes which were totally outside of the realms of possibility of the DC10-40. All-in-all, the DC10-30 has been a resounding success for NWA, and yes its days are drawing to an end slowly as the A330 comes online. It will be a sad day when it finally bows out of service.
 
bobnwa
Posts: 4471
Joined: Fri Dec 22, 2000 12:10 am

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 11:44 pm

Redtailmsp,

Excellent re-cap of the DC-10-40 and DC-10-30. The guys who flew the 40's never had much good to say about them.
 
NWAFA
Posts: 1843
Joined: Wed Dec 31, 2003 10:30 pm

RE: DC-10 30 Vs DC-10 40

Fri Mar 19, 2004 11:50 pm

As a Flight Attendant when I saw a -40 was on my line I figured I would be late due to MCHL problems! Hardly every have problems with -30
THANK YOU FOR FLYING NORTHWEST AIRLINES, WE TRULY APPRECIATE YOUR BUSINESS!
 
Hawaii50
Topic Author
Posts: 7
Joined: Fri Mar 19, 2004 5:08 am

RE: DC-10 30 Vs DC-10 40

Sat Mar 20, 2004 12:43 am

Very good info. Thanks to all that posted. I flew, as a pax, almost exclusively out of Tampa in the late 70's and early 80's when TPA was a mini hub for NW. DC-10-40's to MSP, DTW, BOS and elsewhere. You would go to the gates at TPA back then that NW was at and all that was parked there were 10's and 747's.

When I flew them domestically I never knew there were performance issues. I will say I did hear the occasional compressor stall from the #2 engine, not a pleasant sound for a passenger!

When I would fly to Europe from MSP on the -40 we would on occasion stop in Iceland or ,I think, Greenland to refuel on the return leg, not all the time, just some times.
 
Spoon04
Posts: 179
Joined: Tue Mar 09, 2004 11:15 am

RE: DC-10 30 Vs DC-10 40

Sat Mar 20, 2004 1:49 am

Redtailmsp, thanks for your information re the decent anomaly procedures per the -40. AR385 and Hawaii50... just spoke with my bud (NW DC-10 Captain) on that particular decent procedure. And as Redtailmsp mentioned, the -40 was VERY prone to compressor stalls and subsequent flameout possibilities if the throttles were retarded too quickly. Each crewmember on the -40 was EXTREMELY aware of the procedure for decent. Now then, prior to decent, it was imperative that all bleeds were opened, along with engaging engine anti-ice and ignition. The initial decent rate was 1000 fpm and the Number Two throttle had to be brought back to idle in a time frame NO FASTER THAN TEN SECONDS! Moving the #2 throttle back to idle in less than ten seconds (as Redtailmsp mentioned) could produce a flameout. After #2 was in idle position, another 1000 fpm decent rate could be added and #'s 1 and 3 could be retarded to idle as well (again, VERY CAREFULLY). How'z THAT for a "state of the art" configuration procedure?
Also, as mentioned, the -40 was draconian in scope with respect to the crew's having to manually "hand tune" navaids, and beacon intercepts. All in all, the -40 was a real piece 'o crap compared to the -30'sl
 
User avatar
FlyCaledonian
Posts: 1742
Joined: Mon Dec 29, 2003 6:18 am

RE: DC-10 30 Vs DC-10 40

Sat Mar 20, 2004 5:48 am

Slightly off topic, but does anyone know anything much about the proposed DC-10-50? I believe this was to be a Rolls Royce RB211-524 engined version, offered to BA for longhaul services. In the end it opted for the L1011-500, maintaining commonality with the earlier L1011-1s originally ordered by BEA and the L1011-200s. Was this a serious proposition by McDonnell Douglas, i.e. much design work done? How would it have compared with the DC-10-30, i.e. range, payload, etc? I'm guessing that Rolls Royce engines were proposed with BA using them on the TriStar and the 742s.
Let's Go British Caledonian!
 
AWspicious
Posts: 2780
Joined: Fri Sep 14, 2001 7:47 am

RE: DC-10 30 Vs DC-10 40

Sat Mar 20, 2004 6:39 am

Hawaii Five Oh (...or anyone else, for that matter);
I'm genuinely curious to know what does a compressor stall sound like, and how would a passenger know that was what she or he just heard?
Nevermind political correctness - Envision using your turn signals!
 
Tom in NO
Posts: 6725
Joined: Thu Nov 11, 1999 10:10 am

RE: DC-10 30 Vs DC-10 40

Sat Mar 20, 2004 8:04 am

I'm genuinely curious to know what does a compressor stall sound like

Don't quote me on this, but I think it sounds like a backfire from a car, only much louder.

Tom at MSY
"The criminal ineptitude makes you furious"-Bruce Springsteen, after seeing firsthand the damage from Hurricane Katrina
 
Hawaii50
Topic Author
Posts: 7
Joined: Fri Mar 19, 2004 5:08 am

RE: DC-10 30 Vs DC-10 40

Sat Mar 20, 2004 9:53 am

Tom is right, a very, very loud bang that you could actually feel as well.
 
Hawaii50
Topic Author
Posts: 7
Joined: Fri Mar 19, 2004 5:08 am

RE: DC-10 30 Vs DC-10 40

Mon Mar 22, 2004 12:22 am

I am looking at a book right now that talks about the JT9D engine that NW choose for the DC-10-40 and it states that NW spent $11 million extra for their fleet of 22 DC-10-40's to have the P&W instead of GE. It goes on to say that NW saved $24 million per year in spare parts because of the commonality between their DC-10's and 747's.

It also talks about one of the DC-10's going 8300 flight hours without a single engine issue, which it makes sound like a record. Also about a 7,677 nonstop flight from LA to HKG that their first DC-10-40 made with some FAA people and McDonnell Douglas people onboard, not a full pax flight.

All things said in this book make the -40 sound like the second coming, either that or the book was written with one hell of a slant!
 
BillElliott9
Posts: 237
Joined: Wed Jun 18, 2003 8:10 am

RE: DC-10 30 Vs DC-10 40

Mon Mar 22, 2004 12:48 am

The -40 was an advanced a/c when it was first built....I'm guessing the last one was delivered in '75 at the latest. Keep in mind the jet age wasn't that old when the 10 came out. Comparing them to the newer -30s is not an apples to apples comparison.

I had never read anything negative about the -40 until recently on a.net; Yes, they they were long in the tooth when retired but served NW well for years.





You can fight without ever winning but never really win without a fight.