Fuel Burn Estimates for B-26K and B-25J
Matthew Markham
B-26K (A-26A) and a North American B-25J?
Thanks-
Matt
Peter Stickney
Matthew Markham <matt@jessi%removetoreply%andmatt.net> writes:
> Anyone out there that can give me some fuel burn estimates for a Douglas
> B-26K (A-26A) and a North American B-25J?
Well, the first quastion is (Of course) under what conditions?
But here's a couple of things that might help you ballpark it:
B-25H (PBJ-1H) - Airplane Characteristics and Performance, BuAER, USN,
1 Sept 1944:
1189 US gallons of fuel - Max range, 2030 statute miles at 159 mph.
20% of fuel is held back for warmup, takeoff, climb, and reserve.
So, that gives:
951 gallons of fuel burned, or 5706#
12.76 hours of cruising along, so, for both engines running, 447.2
#/hour of fuel flow, or 76 gal/hr, or 2 miles/gallon :)
Now, the A-26A/B-26K, numbers from the Standard Aircraft
Characteristics Chart, dated Oct '68:
Ferry Mission: 11,430# (1905 US Gal) of fuel less reserve, (let's say 10%)
Range 2346 nm (2702 sm) at 157 kts (180 mph), or 14.90 hrs.
So, 1715 gal burned, or 115.06 gal/hr, both engines, (690 #/hr)
giving 1.36 Nm/gal (1.572 sm/gal)
(if the reserve amount is actually the same as the B-25s, teh numbers
become 102.3 gal/hr (613 #/hr), and 1.53 nm/gal(1.76 sm/gal).
Hope that helps.
--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster
Matthew Markham
Matt
Chris Mark
on the usual. In Italy for mission planning purposes 250 gph was calculated.
That was because over enemy territory flak was brutal. To reduce its effects,
the drill was to cruise at 200 indicated and alter course and altitude every 17
seconds except for the 30 seconds or so over the target, when straight and
level it was. But then a dive away with everything firewalled till clear of
the area, which meant tail end charlie might see 310 trying to keep up. The
whole process was hell on fuel consumption.
In the Pacific they flew 9 hour missions with the J, with an hour reserve.
That was possible because they flew most of the mission with ferry settings and
never climbed more than a few hundred feet.
Nine hours of, depending on crew position, either being deafened by engine and
prop noise, nauseated by exhaust fumes or made seasick by tail waggle. What
fun.
Chris Mark
THOM
<matt@jessi%removetoreply%andmatt.net> wrote:
>Thanks--I was just looking to ballpark it. Thanks for the help!
In the real world that's not possible. He'se right about fuel used
for run-up's take offs etc etc plus what you have when you land. Then
there's density alititude issues, air resistance (parasitic drag) and
ambient temps that all effect range.
THOM
ArtKramr
>From: as...@start.com.au (THOM)
>Date: 6/13/02 6:03 PM Pacific Daylight Time
>Message-id: <3d094097...@news.melbpc.org.au>
Interesting. You didn't say if those planes were loaded with bombs, carried
machine guns with full belts and a full crew. We flew the A-26 A's and as I
remember it we had about 7 hours in the air fully loaded indicating 180mph at
10,000 feet. The numbers you give sound like the plane was being ferried so it
was stripped bare and only carried the pilot. There was no way in hell we could
stay in the air for the 12.76 hours you mentioned. How much manifold pressure
were the R-2800's pulling on cruise?
Arthur Kramer
Visit my WW II B-26 website at:
http://www.coastcomp.com/artkramer
Peter Stickney
artk...@aol.com (ArtKramr) writes:
> Interesting. You didn't say if those planes were loaded with bombs, carried
> machine guns with full belts and a full crew. We flew the A-26 A's and as I
> remember it we had about 7 hours in the air fully loaded indicating 180mph at
> 10,000 feet. The numbers you give sound like the plane was being ferried so it
> was stripped bare and only carried the pilot. There was no way in hell we could
> stay in the air for the 12.76 hours you mentioned. How much manifold pressure
> were the R-2800's pulling on cruise?
He was looking for raw fuel burn numbers, and I didn't want to
complicate things more than I had to. That's my story, and I'm
sticking with it.
(BTW, THOM, the numbers do reflect things like altitude effects, but
are computed for a Standard Day (29.92" hg/1013 mbar 15C/59F))
The numbers are for ferry missions, so thre aren't any bombs or ammo
on board. The fuel burn for a given power setting is going to be the
same, but the cruise speed/cruise altitude is going to vary a bit,
depending on weight. (About 5 mph in the case of the B-25, and anoout
5 kts ('bout 7 mph) for the A-26A.
The A-26A/B-26K he mentions was quite a different plane than the ones
you flew. They were B-26B/C airframes that were rebuilt by On-Mark
Engineering, eho'd been doing executive conversions of Invaders
through the '50s/early '60s. (Before the Bizjets came out, if you
wanted to get people around fast, your company had to have a converted
B-26 or PV-1 (the Navy Ventura - a Lockheed Lodestar with R2800s in
place of teh original R1820s. (There's no substitute for Cubic Inches)
The On-Mark B-26Ks had the later R2800s from a DC-6, no turrets,
rebuilt wings with steel spars (The B-26s sento to Vietnam started
falling apart in the air - Not Good) a bigger rudder, new instruments,
of course, antiskid brakes for better behavior on wet runways, heaters
that worked, wingtip fuel tanks, and a forest of underwing pylons.
They carried about 4,000# more fuel when not carrying bombs.
(IIRC, the A-26C carried about 7,000#)
Oh, and for power settings, that's not picked out in the charts, but
going from P&W's data, and fudging a bit to fir teh fuel burn, I'd say
it was about 2050 RPM/31" Hg, Auto Lean.
Fon an On-Mark '26 with 3500# of bombs, and 7380# of fuel, the
endurance is about 8 hours 20 minutes. (Consider that the later
R2800s were a bit more efficient thah the wartime ones.
Bob McKellar
Peter Stickney wrote:
Speaking for the spotter/geek community, the "K's" were so different after the
rebuild they even got new ser#'s.
http://www.coastcomp.com/av/pres/invaders.htm
Bob McKellar
Alan Minyard
Actually, they were completely different aircraft. When the USAF
renumbered a bunch of a/c, the Martin B-26 was no longer operational,
so the B-26 designation went to the Douglas A-26. These aircraft did
not enter service until Nov 1940, and thus had seen little active
service. About the only similarity was that they both had two radial
engines. No Martin B-26's ever served in Nam.
Al
ArtKramr
not politically correct.
Peter Stickney
Where's I say it was a Martin B-26? The Douglas A-26s were renumbered
to B-26 during the Great Renaming of 1948. Art's unit transitiones
from Martin B-26s to Douglas A-26s in mid '45, just as the war was
ending.
Douglas B-26s were the mainstay of the U.S.A.F.'s Tactical Bombing
force (Light Bomb Force) until the Martin B-57s appeared in ;bout 55
or so. They saw extensive combat in Korea, and were also in USAFE.
A lot of A-26s were supplied to other nations all over the world. The
French used them in Vietnam and Algeria, they saw a lot of use in
SOuth America, and they seem to have been a favorite platform for
CIA-associated "Gray Ops" in te Indian Ocean (Indonesian Crisis, for
instance) Africa (Like the COngo Wars 1 & 2), and the Carribean. (Bay
of Pigs, on both sides).
Invaders were part of the initilal Jungle Jim Air Commando force sent
to Vietnam in th eearly '60s, adn were initially very successful.
They'd had a hard life, by then, and in '63-'64, they started shedding
wings in flight. (The early T-28D conversions had problems, as well.)
This led to their replacement with A-1Es, and the develpment of the
B-26K. By ht etime the Ks were ready, the Vietnamese were pretty
comfortable with the A-1s, so they were used for night interdiction
over the Ho Chi Minh Trail, mostly in Laos. They were based out of
Thailand. Treaty restrictions (at that time) made basing bombers in
Thailand impossible, so with a swish of a pen, teh B-26Ks were
re-redesignated A-26As. (Not that it mattered, 'cause it wasn't too
much longer before ther ewere B-52s a U-Tapao. I suppose the SAC guys
balked at having the Big Stick restrung as a Light Bomber.
Peter Stickney
artk...@aol.com (ArtKramr) writes:
> The A-26 was reenamaed "B" because some in congress thought that "attack" was
> not politically correct.
Well, Bureaucratically Correct, anyway. When the Air Force became
independant, they decided that they were going to restring the
designators around to make them more Modern and Efficient.
Instead of th old mish-mash of single and two letter combinations,
they went to the same sort of system used now: A basic type designator
with a prefix for function. That's when 'P for Pursuit' got swapped
with 'F for Fighter'. (And 'F' for Ph[F]otorecon became RF, RB, or RC
as appropriate) All the OA's (Observation Amphibians),
which weren't doing any observing anyway, became 'A's, most of them
with an 'S' prefix for Search and Rescue. (As in teh OA-10 Catalina
and OA-16 Albatross). The Light Bomber category. (The old 'A'
category, was split up, with single engine light bombers (Basically
only a few A-24 Dauntlesses, used as hacks) becoming Fighters. (F-24),
and multi-engine Light Bombers becoming Bs. (The A-20s were long gone,
and the Martin B-26s didn't last long past the end of the war, so the
end result was that it was only the A-26 got restrung. (Of airplanes
already flying - there were some jst light bomber projects that aere
redesignated before they were built).
Art, you might like to know - Martin recently delivered the last Titan
Heavy Launch booster a few weeks back. The article number for the
stack is "B-26". It's due to launch in 2004.
Alan Minyard
Gee, tell that to all the guys who flew the A-6, A-7, A-10.
Al Minyard
Alan Minyard
>Where's I say it was a Martin B-26? The Douglas A-26s were renumbered
>to B-26 during the Great Renaming of 1948. Art's unit transitiones
>from Martin B-26s to Douglas A-26s in mid '45, just as the war was
>ending.
>
Sorry Peter, I misread. I should have known that you would not make
such a mistake. I got excited when I though that I had caught you on
one :-)
Al Minyard
ArtKramr
>was
>>not politically correct.
>>
>>Arthur Kramer
>>Visit my WW II B-26 website at:
>>http://www.coastcomp.com/artkramer
>
>Gee, tell that to all the guys who flew the A-6, A-7, A-10.
>
>Al Minyard
>
Things change over the years.
ArtKramr
>Date: 6/14/02 2:43 PM Pacific Daylight Time
>Message-id: <kp5dea...@Mineshaft.att.net>
That is both interesting and surprising. We planned to have our reunion (the
344th) in Baltimore (The B-26 was called the Baltimore Whore) and the Martin
company didn't want to hear a thing about it. They said they wouldn't
cooperate. It was as though they were ashamed of the Marauder and all the men
it killed. So now the appelation B-26 lives on. Who knows, maybe forever.
(sigh)
Bill Shatzer
On 14 Jun 2002, ArtKramr wrote:
> The A-26 was reenamaed "B" because some in congress thought
> that "attack" was not politically correct.
Seems unlikely that congress was responsible as about the
same time, the Navy was redesignating all its bomber types
as "attack" - to wit, A1D Skyraider, AJ-1 Savage, AU-1, etc.
Cheers and all,
Peter Stickney
I'm hardly infallable. It is a mistake that peole make quite often.
Ferinstance, the otherwise fairly decent Korenean War era Gamesim "Mig
Alley" is chock-a-block with Martin B-26s. (Beautifully rendered, but
wrong.)
I won't mention the time back in my Kadet Daze when we were playing
"ID the Airplane: at Wright-Pat, while waiting for our ride home to
show up (AFRES C-123K), and I called a T-39 as an F-104.
Or when I landed the J3 on the beach, & left it parked on the firm
sand, & forgot all about that tide thingy.
David Lentz
The designation of a particular aircraft had little to do with
the aircraft's mission, but depended on who owned the aircraft.
For example a light bomber, the F-117, was designed as if it were
a fighter to denote it was owned by TAC and not SAC. Likewise
the B-65 and B-68 were designed as bomber to reflect the facts
they were owned by SAC and the USAF.
David
--
qyra...@ebpurfgre.ee.pbz
Peter Stickney
'Twarnt always teh case, though. Throughout the 1950s, TAC, USAFE,
and PACAF had their own dedicated Light Bombers, to wit the Douglas
B-26, the B-45, the B-57, and the B-66. They were flown by Tactical
Bomb Wings, and, in he case of the B-45, B-57, and B-66, they spent
most of their bomber careers as nuclear delivery platforms. The
development of Fighter-Bombers that could carry the same nuclear
punch, but with a better ability to reach their expected target (The
F-84F and F-100D, in particular, but followed by the F-101A/C, F-105
and F-4), and ehich could perform other tasks led to Tactical Bombers
going out of fashion in the late '50s/early '60s. (It's perhaps
fortunate that in many ways, PACAF was on the short end of the stick -
they still had a couple of B-57 equipped Tactical Bomb Squadrons on
hand at the beginning of the Vietnam War (Albeit attached to Tactical
Fighter Wings), where they proved to be very useful.
ArtKramr
>From: p-sti...@worldnet.att.net (Peter Stickney)
>Message-id: <dkpfea...@Mineshaft.local.net>
I remember the first day they delivered the A-26's to us, we thought we died
and went to heaven On the first flight we thought we were in heaven.
Peter Stickney
artk...@aol.com (ArtKramr) writes:
> I remember the first day they delivered the A-26's to us, we thought we died
> and went to heaven On the first flight we thought we were in heaven.
I'll bet they were, Art! (I almost got to fly in an Invader, I got as
far as sitting in the right seat, but out Return time meant I'd have been
walking home - now I kick myself - the walk would have done me good)
I've hung around them a bit, and I've also crawled through the Air
Force Museum's Marauder. The Marauder is quite a machine, but it's
still very much a 1930's airplane. The Invader still seems very
modern. Sort of the same impressions you'd get going from a '36
Packard to a '56 Cadillac. I've seen Invaders tossed around pretty
well for a big twin. (Watching them being used for Borate Bombing out
West) Your pilots must have thought that they wer finally flying
fighters.
The B-29 struck me in much the same way. When the CAF goes
barnstorming with their bombers, seeing the B-29 next to a B-17 or
B-24 really drives home how much things changed during the war.
--
Pete Stickney
ArtKramr
>From: p-sti...@worldnet.att.net (Peter Stickney)
>Message-id: <r4dgea...@Mineshaft.local.net>
Well Pete if you crawled through a Marauder you realise how tough the
bombardiers had it. To get to the nose the copilot had to slide his seat back,
grab your chute harness so you wouldn't get tangled on the engine controls and
guide you asoyou crawled through to the nose. You were trapped in the nose
unless the co pilot slid his spring loaded seat back and helped you out. In an
emergency the bombardier was the last to get out if ever. In the A-26 there was
a trap door right under my feet, Twist a handle and I was out. What a relief.
ArtKramr
>From: p-sti...@worldnet.att.net (Peter Stickney)
>Date: 6/15/02 6:55 PM Pacific Daylight Time
>Message-id: <r4dgea...@Mineshaft.local.net>
>
A few more points on the B-26 vs the A-26. You gotta remember that our B-26
Marauders were war wearies. They were dented patched with crazed Plexiglas and
they stank of vomit, urine and cordite. The Invaders were brand new, smelled
like a leather shop and gleamed in the sun. Ah it was a full life. ( grin)