Boeing wants to sell nice new aircraft they dont make as much money keeping up nice old aircraft

Would be ashame to scrap them. Just as an example, comparing the DC-8-62F with the B757F (not to mention the -73F which is larger/heavier but with a reduction of 30% in fuel burn compared to the -62F).

The B757F has high payload-range restrictions compared to the DC-8-62F (and -63/-73F). The B757F carries just over 35 tons for approximately 4 flight hours whereas the DC-8-62F carries 42 tons for over 7.5 flight hours. Additionally, the higher lease rates of the B757 make its overall operating costs more expensive than the DC-8's.

I read in a report some time ago that for the B757 to equate the total operating cost of the -62F, the fuel price would have to increase to $2.50 per USG. Perhaps the "8" may still have a future when biofuels catch on?

Instead of scrapping the "8" -60/-70 series, Boeing should put at least one of each in the Museum of Flight and preserve them well.

Green-dot

35 tons for 4 hours...

From Boeing website:

Up to 15 containers or pallets, each measuring 88 by 125 inches (223 by 317 centimeters) at the base, can be accommodated on the main deck of the 757F. Total main-deck container volume is 6,600 cubic feet (187 cubic meters) and the two lower holds of the airplane provide 1,830 cubic feet (51.8 cubic meters) for bulk loading. These provide a combined maximum revenue payload capability of 87,700 pounds (39,780 kilograms) including container weight. When carrying the maximum load, the 757F has a range of about 2,900 nautical miles (5,371 kilometers).

That makes it 725 knots/hr!

Let's face it folks, the 757 is just a two-engined 707.
But worse!

Seem to remember only 12 for the 707...but it will fly further.
Been there, done that, have T shirt...etc

Not really fair to compare the 757 to the DC8 or 707 for that matter, it is in a totally different weight and payload category.



What would be more realistic and interesting would be to compare both older generation Aircraft to the 767-300F.

Well our B757 (freighter built by Boeing, not converted) has a max payload of 39 tons and change (15 pallets). With fuel on top of that (about 24 tons), we´ll go about 5,5 hrs, landing with about 4 tons.

Not to far from the DC-8-55F if I recall correctly, same number of pallets, OEW about 140k lbs(if memory serves,many a loadsheed handwritten...) payload 100k lbs (45 tons) and fuel 85k for a MTOW of 325k lbs. That would have meant a range of about 5,5 hrs burning about 13,500 pr. hr and landing with 10,000 lbs.

Numbers are not too different really.:ok:

Green-dot

I've seen 2.50 USD/USG figure more than 10 years ago and that was 62/63F vs 72/73F, have you seen the same material by any chance?

DC8 is maintenance extensive airplane comparing to next generation (like 757) and if you want to maintain it properly you would not be competitive on the market which is almost solely driven by $/kg/nm.

There is always a good reason why this or that aircraft model was phased out from so called "developed countries" fleets. Africa is a different story.

Can anyone compare the 763F to the DC8 73 F ? !

Why we should compare 73F to 763F? 763F is almost 80% more volume than 73F and aircargo is sold on volumetric payload basis. 73F can carry only 40 volumetric tons, while 763F is around 75 volumetric tons.

If you aviation geniuses have it all figured out that an old decrepit DC-8 / 707of whatever model / vintage is any better than a 757 F economically , then perhaps you should put an application in to AIG , Citi , UBS , or any of these other institutions that could use your accounting skills. I`m sure you could convince both Boeing and Airbus to restart up the line...Quit living in the past. Nostalgia doesn`t pay , economics do. These a/c belong in a museum.

'Pterodactyls' DC8s , 722 , 732 , 742 etc
 

A friend of mine runs a fleet of B722 and 732 cargo aircraft in Asia and he never sleeps during the week , they're constantly going AoG from minor avionic / instrument and electrical snags .

Cheap to buy , parts not too badly priced now as the market is flooded with spares but trying to stick to a schedule , what a nightmare !

If you need 2 aircraft you buy 3 and have one as a back up and maintenance spare

Agree with the other posters , these older generation jets aren't economic for high utilisation scheduled cargo ops. For ad hoc charter or other ops where the utilisation is low and the aircraft is waiting on the ground a lot the lower capital costs make sense and they are still good in that role.


-

I had not realised the 763 had that much more volumetric capacity.However the 73F gross weight is fairly close to the 763 and the fuel capacity is nearly identical.

It is certainly a closer comparison than the the 75F and illustrates the efficiency of the (more) modern design.


Make no mistake, I am a great admirer of the DC8 in general and very impressed with its longevity, even before the CFM 56 retrofit it was a long range machine, with the new fans it rightfully gained an extended new lease on life with its stunning performance.

I wonder how many 707's would be around if it had the taller gear of the -8
allowing a similar retrofit, the USAF reengined their tankers but the civilian market just didnt seem to like it.

I suspect not all that many.
The early build quality of the 707 (especially the -320 straightpipe model) was not all that good, due to skin fatigue cracking issues.
Later models were better built.
I suspect the DC-8 was better still.

There is another problem: C & D checks, landing gear, many components are calender-driven on old machines, so if you are on low utilisation, maintenance costs per hour becoming very high, I think most remaining operators of those old aircraft are not considering to do next D check, just scrap or park the airframe. Again CPCP, aging aircraft programmes and some ADs making them not viable for "developed" countries operations, but with some sort of creative approach and buddies in Kinshasa CAA some people still can make money out of it.

True , then they go and buy another one with a couple of years to run and park that one at the next C or D check

Supply will dry out soon, I'm not sufficiently familiar with DC8 but I believe D-check is anyway within 8 to 12 years limit and not so many of them done in past years.

According to the Dutch aviation news site (Luchtvaartnieuws: dagelijks actueel luchtvaartnieuws) the DC8 operated the last commercial flight for UPS on 12/05/2009 from Philadelphia to Louisville.