DC-8 two-engine ferry?
Thread Starter
Joined: Feb 2001
Posts: 1,117
Likes: 14
From: Europe
DC-8 two-engine ferry?
While reading "Airline Cargo Management" March 2005 issue I have noticed the article on how airlines are reducing the fuel burn. Here is the small extraction:
[Arrow Air / Miami]
...Arrow has lowered its fuel consumption fleetwide by 12% over the past year, says Visconti. This has been achieved by measures such as two-engine ferry flights with its four-engined DC-8, expedited taxiing times at airports, restricted use of APU on its DC-10s, blah-blah-blah..
2-engine ferry flights on DC-8?
What does it exactly mean?
[Arrow Air / Miami]
...Arrow has lowered its fuel consumption fleetwide by 12% over the past year, says Visconti. This has been achieved by measures such as two-engine ferry flights with its four-engined DC-8, expedited taxiing times at airports, restricted use of APU on its DC-10s, blah-blah-blah..
2-engine ferry flights on DC-8?
What does it exactly mean?
Joined: May 2002
Posts: 2,242
Likes: 0
From: Australia
I think what it means is that on empty legs they will get airborne on four and when at the selcted cruise level they will shut down two engines, relighting them during the descent and land with four running.
Joined: Feb 2005
Posts: 4,581
Likes: 0
From: flyover country USA
Ferry? or taxi?
I think we have some journalistic license encroaching here - almost certainly meaning "2-engine taxi". I cannot understand how ANY kind of ferry flight saves Jet A anyway.
My favorite example of media brilliance was a photo caption - a helicopter on a dolly being hand-pushed across the ramp. The writer tells us that the chopper was being "push-started"!!!!
My favorite example of media brilliance was a photo caption - a helicopter on a dolly being hand-pushed across the ramp. The writer tells us that the chopper was being "push-started"!!!!
The Reverend
Joined: Oct 1999
Posts: 2,020
Likes: 0
From: Sydney,NSW,Australia
No way Jose! Total fuel burn at the lower two engine flight levels , even at low zero fuel weights will surely exceed four engine cruise fuel flows at four engine levels. Just look at the performance charts.
Joined: Oct 2002
Aviation Qualifications: PPL
Posts: 8,208
Likes: 351
From: London UK
Not sure about the FAA position though!
Joined: Mar 2000
Posts: 313
Likes: 1
From: NE Surrey, UK
I believe that RAF Javelins would shut down one engine to conserve fuel when on high altitude loiter over the North Sea during the Cold War. When Ivan the Bear hove into radar view the engine would be relit for intercept and escort away from the coast.
Not sure if this works for more modern types though.....
Not sure if this works for more modern types though.....
ex-Tanker
Joined: Apr 2000
Posts: 907
Likes: 0
From: Luton Beds UK
If you are flying cruise FL, you are for sure better off on 4 than 3 or less engines.
If you are flying at low level - for instance in the Nimrod anti sub role - you will save by shutting 1 (2 depending on weight) down.
If you are flying at low level - for instance in the Nimrod anti sub role - you will save by shutting 1 (2 depending on weight) down.
Joined: Apr 2004
Posts: 258
Likes: 0
From: vancouver oldebloke
Although nonstandarn three engine ferries were performed on the DC8/B707-747/and the coronado(ask Spantax)..Nonstandard in that the COA validity was suspect.I did 5 in 10 years on the 8,just to move the aircraft for engine changes....Several restrictions applied,reduced flap(higher speeds for 2 eng'VMC)reduced weight,240000,instead of the gross 352000..Takeoff thrust on the assymetric engine had to set by VR,and Captains were required to 'demonstrate' the proc' n the regulars Sim's.Eventually the procedure was 'phased' out,with the distribution of engines through the network..
Some 'charter' carriers were known to'idle' #3 in cruise to avoid unnescessary fuel stops...
Some 'charter' carriers were known to'idle' #3 in cruise to avoid unnescessary fuel stops...
Joined: Dec 2000
Aviation Qualifications: ATPL
Posts: 1,271
Likes: 40
From: Various
Didn't Alderney Air Charter do single engine ferries? I think I recall the boss (Pete Moss?) saying that if the Cesna 337 lost a donkey on the island that he would unbolt the prop, bolt the spinner back on, strap the prop to the pax seat and ferry the bird back to the mainland.
Ahhhhhhh! the good ol' days!!!!!!!!!!!!
Ahhhhhhh! the good ol' days!!!!!!!!!!!!
Short Blunt Shock
Joined: Jul 2003
Posts: 631
Likes: 0
From: UK
Grimrods often throttle back an inboard whilst doing a LL patrol or SAR sortie over the sea- this does save fuel, but I believe it's more to do with having instant(ish) throttle response in the event of having to climb away fast, since they are so over-powered they would have to be throttled back a long way on all 4, with the associated spool-up time.
3-engine take-offs are perfectly possible. We do them as a matter of course in Albert (simulated in the aircraft, or real in the sim) - it is a basic training requirement. Plenty have been done for real as well.
16B
3-engine take-offs are perfectly possible. We do them as a matter of course in Albert (simulated in the aircraft, or real in the sim) - it is a basic training requirement. Plenty have been done for real as well.
16B
Joined: Feb 2005
Posts: 4,581
Likes: 0
From: flyover country USA
unbolt the prop
Almost 50 years ago, when the Aero Commander was just entering the market, the factory unbolted one prop and stowed it in the cabin, then ferried the bird on one from OKC to TEB to the business aircraft convention.
Made great press!
Made great press!
Joined: Jun 2004
Posts: 1,843
Likes: 0
From: Australia
2 emgines shut down at quite low levels and appropriate weights to sustain a further engine failure, a la Nomrod, wonderful for ENDURANCE and loiter capabilities, but an absolute DISASTER for range capability.
Even if it were safe AND legal for civil operations, there would be absolutely nothing to gain in improved range capability, i.e. a lesser fuel burn for a specific ferry difference. One engine shut down out of 4 may make a difference.
Old Smokey
Even if it were safe AND legal for civil operations, there would be absolutely nothing to gain in improved range capability, i.e. a lesser fuel burn for a specific ferry difference. One engine shut down out of 4 may make a difference.
Old Smokey
Joined: Jul 2000
Posts: 114
Likes: 0
From: Robin Hood country.
To taxi with inboard engines running ( they're the ones with the hydraulic pumps) with a delayed start for the outboards is standard practice. Typically saves in the order of 1000lbs of fuel and is smiled upon by the bean counters.
A Three engine take-off and ferry for maintenance under a special operating certificate with a crew especially trained for the stunt ( things can/do get squirrelly as asymmetrical power is applied on the take-off roll) is also standard practice.
Shutting two down enroute increases endurance but knocks the specific fuel flow down south, absolutely no commercial advantage to it. The bean counters would soon start screaming.
A DC-8 will stay airborne with just one engine running - at least in the sim. If shutting down two were to make money think of the savings to be had with three blowing in the wind.
A Three engine take-off and ferry for maintenance under a special operating certificate with a crew especially trained for the stunt ( things can/do get squirrelly as asymmetrical power is applied on the take-off roll) is also standard practice.
Shutting two down enroute increases endurance but knocks the specific fuel flow down south, absolutely no commercial advantage to it. The bean counters would soon start screaming.
A DC-8 will stay airborne with just one engine running - at least in the sim. If shutting down two were to make money think of the savings to be had with three blowing in the wind.