707 Vs DC8

[AvroGuy]

So here is my question, why is it that the DC-8 has survived as a cargo carrier in the states but the 707 hasn't?

 

[GRAAB HIRBOUBI]

707 / Dc8

If you look at the fusealage, you will see that the bottom slopes gently up to the tailcone on the 707. The DC8 goes more straight back and has a sharper slope towards the tail cone.

More cubic cargo space under the main floor on the DC8 than the 707. Granted I don't think its that much but thats what a DC8 Capt at UPS told me about 15 years ago.

Probably wrong but I have heard this from more than 1 source.

Former AVRO Guy Now SAAB Slave

 

[AirCobra]

DC-8 Series 61 and Super 72 are larger than the largest 707 model the 320C. Airlines like Delta and United had already modified DC-8's with new more powerful and fuel efficient GE engines by the time cargo companies bought them, no such civil mod for the 707. The lower deck of the DC-8 has a container system making loading/unloading quicker.

 

[J3CubDriver]

It's a Douglas. Look at all the DC-8's, DC-9, DC-10's still flying. Douglas overbuilt everything, plus kept it simple. All cables. The inside of an 8 looks like a harp. Cables everywhere. The 707 or early 737 weren't built as tough. The early Boeing had skin problems. The DC-8's days are numbered now. They are getting very expensive to C check. Over a million dollar these days. One tough plane.

 

[DC8 Flyer]

DC8s rule, Boeings drool, nuff said.

 

[hawkerjet]

It's a Douglas. Look at all the DC-8's, DC-9, DC-10's still flying. Douglas overbuilt everything, plus kept it simple. All cables. The inside of an 8 looks like a harp. Cables everywhere. The 707 or early 737 weren't built as tough. The early Boeing had skin problems. The DC-8's days are numbered now. They are getting very expensive to C check. Over a million dollar these days. One tough plane.

I once heard a DC-8 captain refer to them as the Douglas Cable Company. One pretty tough bird.

 

[landlover]

best nickname for a DC-8, "the ocho" courtesy of the movie dodgeball.

 

[EMBATP]

707

of course it could have something to do with the usaf buying buttloads of 707/720s off the used market when they were doing the kc-135 e mods.....

 

[Waldom]

The DC-8 was designed with a taller landing gear, so the fuselage could be stretched in later versions. The stretched versions hold 18 pallets or igloos.

The biggest B-707 (the -320) only holds 12 pallets for essentially the same operating costs. That airplane was designed with a shorter landing gear than the Douglas. If its fuselage was stretched as long as that of the DC-8-61/71 or -63/73, the tail would strike the runway at 4 or 5 degrees nose up attitude and the airplane could not take off. Boeing did learn from there mistakes, however. Ever notice how tall the landing gear is on the 757 and later designs?

One other advantage the Douglas product has is the fact that its systems are designed with stone-ax technology. Simple equals reliable and long-lasting. Douglas designers did not go the elegant and sophisticated engineering route: they built it like a locomotive.

 

[HeavyjetDC8]

Have to agree with Waldom: the DC8 could be stretched whereas the 707 couldn't without hitting the rear end on takeoff. There's also too much electrical stuff on the 707 - all very nice when new and working properly but over time the cable systems of the DC8 have repeatedly taken a licking and kept on ticking.

In more recent years restrictions on approach flap extension and the prohibiting of inflight reverse (to prevent airframe fatigue) have made the DC8 a bit of a handful in the descent planning department. It'll probably be the cost of maintenance, especially C checks, that finally kill the aircraft off.

 

[L'il J.Seinfeld]

of course it could have something to do with the usaf buying buttloads of 707/720s off the used market when they were doing the kc-135 e mods.....

The KC-135 and the 707 are not the same airplane. The USAF bought up some 707s for the E-8s, but the 707 and KC-135 are mutually exclusive. -135 drivers get 707/720 type ratings but the respective airplanes have different fuslelages, have drastically different systems, and the -135 never had an FE.

 

[B767Inst]

The KC-135 and the 707 are not the same airplane. The USAF bought up some 707s for the E-8s, but the 707 and KC-135 are mutually exclusive. -135 drivers get 707/720 type ratings but the respective airplanes have different fuslelages, have drastically different systems, and the -135 never had an FE.

OK..I guess I'll get to be the first to disagree with your post. The Air Force did buy a large number of 707's to use for parts on the -135 fleet. Specifically the JT3D turbo fan engines. And as to the second part of your post, as a previously qualified -135 F.E., I take umbrage. The Air Force used FE's on WC-135, VC-135, and some EC-135's.

 

[GittinFatter]

I spent just shy of 3000 hours as a DC-8 engineer. It truely is a remarkable machine but rather unrefined. I have never flown the 707 or DC-8 as a pilot, but the folks that have flown both, much prefer flying the boeing.I guess its smooth easy to fly plane, whereas the DC-8 is a big mack truck!

 

[afpa]

Just to clarify, you can still use inflight reverse on the inboards on the DC-8.

 

[GogglesPisano]

. The 707 or early 737 weren't built as tough. The early Boeing had skin problems.

Joe Patroni would disagree.

 

[FearlessFreep]

Diesel Eight!

Tough old bird. From my understandings the 707's also have some corrosion issues and from what I have heard a life-limited airframe, the -8 does not.

A 61/71 & 63/73 -8 is a pretty big aircraft. All of those models are categorized as "heavies" (> 300,000 # MGTOW) With the CFM-56's mounted they are very efficient. I don't think that UPS is planning to retire theirs any time soon. If I remember correctly UPS is currently operating the largest fleet of -8's. From my understanding they have all been updated with glass cockpits - EADI, EHSI, FMS

 

[1800 RVR]

If I remember correctly UPS is currently operating the largest fleet of -8's. From my understanding they have all been updated with glass cockpits - EADI, EHSI, FMS

No FMS on ours. We still use the good ole' INS.

 

[L'il J.Seinfeld]

OK..I guess I'll get to be the first to disagree with your post. The Air Force did buy a large number of 707's to use for parts on the -135 fleet. Specifically the JT3D turbo fan engines. And as to the second part of your post, as a previously qualified -135 F.E., I take umbrage. The Air Force used FE's on WC-135, VC-135, and some EC-135's.

Yeah, I agree with what you said above. I was trying to make the distinction that the 707 and Kc-135 are not the same plane. I was not aware that the USAF bought 707s to use as spare parts for the -135 fleet. But you cannot buy a used 707 and turn it into a KC-135.

 

[b707guy]

While I understand your position, B767Inst, no umbrage should be taken regarding the comment that C-135s never had FEs. You've been there, so you know what L'il J said is semi-correct in that the aircraft never had a dedicated FE panel. It's not exactly common knowledge that various AF commands did and still do use a PFE on the 135s. Don't get me wrong - I always appreciated the reduced workload as a pilot with W&B, performance and with the overhead panel for pressurization and electrics in those cases, and the only complaint, if you want to call it that, is that it could get a bit awkward at times with the FE reaching over the throttles to handle to fuel panel. And you can't say that the fold-away jumpseat was exactly first rate. It wasn't even really rated for crash loads. The plane was designed to be operated in wartime with two pilots, a nav, and a boom operator.

Back to the topic, Waldom and HeavyJet's comments hit the nail on the head regarding the landing gear. And while I still miss flying the 707 and the C-135, I've sure come to appreciate the bulletproof but Rube Goldberg design philosophy of the DC-8. It's a great freighter.

 

[DC8 Flyer]

While I understand your position, B767Inst, no umbrage should be taken regarding the comment that C-135s never had FEs. You've been there, so you know what L'il J said is semi-correct in that the aircraft never had a dedicated FE panel. It's not exactly common knowledge that various AF commands did and still do use a PFE on the 135s. Don't get me wrong - I always appreciated the reduced workload as a pilot with W&B, performance and with the overhead panel for pressurization and electrics in those cases, and the only complaint, if you want to call it that, is that it could get a bit awkward at times with the FE reaching over the throttles to handle to fuel panel. And you can't say that the fold-away jumpseat was exactly first rate. It wasn't even really rated for crash loads. The plane was designed to be operated in wartime with two pilots, a nav, and a boom operator.

Back to the topic, Waldom and HeavyJet's comments hit the nail on the head regarding the landing gear. And while I still miss flying the 707 and the C-135, I've sure come to appreciate the bulletproof but Rube Goldberg design philosophy of the DC-8. It's a great freighter.

God that is a beautifule -8 in the background....