DC8 vs B707

[pegleg]

Can any of the older fraternity please explain how the DC8 had pretty much the same performance as the B707 in terms of payload/range and yet did not have leading edge devices.
Many tks

[quid]

I have flown them both. The DC-8 has leading edge slots to improve low speed handling.

Once the wings are clean, the devices have no effect on range, so I don't really understand what you're asking here. ??

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[pegleg]

Hello Quid,

Not having had the pleasure of flying either, I must have been under the misapprehension that the DC8 family were never fitted with leading edge devices of any kind. I of course bow to your experience and declare the question therefore irrelevant. As a matter of interest which of the two did you prefer to fly?

Cheers

[m&v]

flew the 8,and later the 727(both for 10yrs)the dc8 didn't sweep the wing as far back as Boeing,so it had (with the aforementioned slots-with flap extension)acceptable "slow speed"(approach)characteristics.Boeing develped the"07"originally for the USAF as a tanker(kc135)needing the higher speed wing-requirering the Led's(slats/flaps) for approach handling.Cruise of M.80+ to 135k approach.This successful concept was carried over to the "27"(providing it with some 4000 airports in the US).with the call for flaps15,one recieved 48% of wing dissasembly..Both the DC8 and the B727 were excellent aircraft.The 27 as a pilots aircraft(even on one engine)the Eight as the last economic trans ocean aircraft(the 63' burn't 11000lbs/hr for 200pax at M82)

[quid]

It's been many years since the 707/720. I now fly the DC-8. It's always a challenge. I don't remember enough to pick one over the other.

My favorite - no contest. It's the 727.

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[Jim lovell]

According to Jane's encyclopedia of world aircraft here are the comparisons:
Boeing 707-320C
powerplant:4*JT3D-7
max speed:627 mph
service ceiling: 39,000 ft
range: 5,755 miles
MTOW: 151318 kg
wing sweepback= 35 degrees

Douglas DC-8-63
powerplant: 4*JT3D-7
max speed: 600 mph
range: 4,500 miles
MTOW: 158,757 kg

[Vmu]

But as far as looks go, the DC8-71 wins hands down!!!

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"Recovery was marginal..."

[Sleepless_Knight]

Just checked my manuals and the 8 has 30° sweep at 25% chord, so according to the janes info it is definitely less, that would seem to answer the question. Just to clarify though, pegleg, your question is not irrellevant. The slots on the 8 are only on small portions of the wing just inboard of the pylons. They are much less extensive than the LEDs on the 707. I have often asked myself the same question, now I know! Thanks guys!