Unbuilt ASW/MARPAT versions of airliners?

Jemiba said:
From Aviation Week 1977 1-9 a Boeing derivative of the 727, still 3 engined, but
with the tail side mounted engines moved to pods under the wings. Any explanation
why ? Lower noise level in the cabin, for a better acoustic environment ? ???

I can think of three possibilities:

* There are new engines. Perhaps the rear structure would require too much beefing up to support all three of them.

* Space needed for a MAD sting. Support structure and systems for two side engines could make this difficult.

* Perhaps Boeing was also hoping for a follow-on tanker order. Moving those two engines to the wing frees the rear underside for a refuelling boom.

I'm not sure, but the wing-mounted engines appear to have a higher bypass ratio than the 727's standard JT8Ds, I suspect the middle engine was a variant of the same engine, but with a reduced bypass ration to work with the existing inlet (the redesign of that aspect would be expensive). This would free up aft fuselage "real estate" for other systems that they might want to install. Moving the engines like that also greatly reduces the probabability that a catastrophic rotor failure on one engine will take out another engine; I suspect this would be a major concern to the Navy. Loo9king at the underwings engine nacelles, though, I have to wonder if they lengthened the landing gear legs because those nacelles seem to hang farther below the wing than the ones on the 737-100/-200.
Sorry for reviving an old thread, but these articles were lostfor quite a time
and I'm not sure, that it won't happen again... ::)
A maritime patrol version of the Xian Y-7, designated Y-7-2000BF.
(from Aircraft Illustrated February 2001)


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the Airbus A-320MPA.



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A319MPA (from Flight) and A319MPA/A320MPA comparison.


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Was discovered in lot of Lockheed photos I've obtained recently. Think that would look nice here.


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"757 ASW"- Boeing candidate for the LRAACA competition based on the 757.


Orion 21

Source: P-3 to P-8 - an air-sea saga


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Anyone know whatever became of the ASW proposal of the Tupolev Tu-204 from a few years ago?


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Some very interesting designs I had not seen or heard of before!
Does anyone have a three-view drawing of the Lockheed P-7 and the McDonnell Douglas P-9 LRAACA designs????

Thanks in advance

Model of Lockheed P-7 by Pacmin found on eBay.

A extremely rare factory made, 1:100 Scale, USN Lockheed proposed P-7A sub-hunter Desk Model by Pacmin. The model is made of solid, hard injected molded plastic and resin composite type materials. The model airplane measures approximately 16" long x 14.5" wingspan x 5" tall. Walnut stand included. The model is in brand new condition but there is no original box.

URL: http://cgi.ebay.com/Rare-Pacmin-desk-factory-1-100-Lockheed-P-7A-USN-model-/160463347769?cmd=ViewItem&pt=LH_DefaultDomain_0&hash=item255c5c6039


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Some info on the P-7A.
Flighcrew of five and a mission crew of five. Armament on 12 hardpoints and on the bay with a maximum load of 38,400lbs. 120 sonobuoys in pre-loaded packs fore and aft of wing with 38 inside the cabin for loading into pressurised chutes and up to 150 more on dense packs of eight hardpoints. Avionics included Texas Instruments APS-137(V) radar, Texas Instruments ASQ-81(V)1 MAD, FLIR, LLTV, dual INS, Doppler navigation, Litton ALR-77 ESM and cameras. Eninges were to be the 5,000ehp GE T407-GE-400 with total internal fuel capacity of 66,350lbs. Empty weight 73,750lbs and MTOW 171,000lbs. Max speed 473mph+ at 15,000ft, intial climb 2,890+ ft per min, service ceiling 28,000ft and radius 1,840 miles for a patrol of 5 hours 54 mins. Span 32051m and length 37.49m.
In 1989 it was thought a prototype would fly in late 1991 with service entry in 1994. Likely production numbers then looked like 125+ for the USN and 12 for West Germany.

Somehow given the length of time the P-3C has operated I think the P-7A might have made a useful type given the explosion of MPA sales since the 1990s even though European nations these days tend to sell off thier MPA fleets and shrink them down.
flateric said:
Was discovered in lot of Lockheed photos I've obtained recently. Think that would look nice here.
Note the Phoenix (?!?!?!?!) on the outermost hardpoints. It's not Maverick; far too fat.
Howedar said:
flateric said:
Was discovered in lot of Lockheed photos I've obtained recently. Think that would look nice here.
Note the Phoenix (?!?!?!?!) on the outermost hardpoints. It's not Maverick; far too fat.
AGM-84 Harpoon
Nope, the outer ones are not Harpoon. The inner ones certainly are, but the two outermost weapons on each wing have a long tapered delta-wing that is distinctly different from Harpoon. I'd say it probably is meant to be Maverick, or possibly the longer, air-breathing, Longhorn variant.

Here's a link to a nice walk-around of a P-3B with both Harpoon and Maverick carried, showing that they look quite similar in diameter. Remember that it's only about 1.5 inches difference (13.5-in diameter for Harpoon, 12-in for Maverick).

mea culpa.

I was looking at the wrong picture. Yes, I agree with TomS, it seems to be a AGM-65 Maverick.
Must have been late at night; for some reason I had a huge diameter difference in my head between Maverick and Harpoon.
Some of you expressed the wish to see a three-view arrangement of the P-7A... Well, this is not quite it, but the closest I can get so far. Here is a two-view of the P-7A as well as a cutaway view which were both scanned and enhanced from the original P-7A press kit. Loads more stuff in it but it will take some time to work the other pages so stay tuned if you're interested, I'll add it in the following weeks.


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In late 1988 ATR and Dassault-Breguet proposed the Petrel 42/ Petrel 72 MPA using the airframe of either the ATR 42 or the ATR 72 with an avionics suite similar to that of the Atlantique 2. The Petrel 42 would be primarily an anti-ship variant with AM39 Exocet mounted on stub wings mounted on the undercarriage fairings. The Petrel 72 would be an ASW aircraft with up to four torpedoes. Both would have an under-nose FLIR turret and ventral Iguane radar mounted roughly aft of the cockpit. The Petrel 72 would have sonobouys too. A picture I have in Jane's Civil and Military Upgrades 1993-94 has just one window forward on the starboard side (an escape hatch) and five aft along with a door, presumably for the crew rest area.


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I don't have photos, but I do know there was a Gulfstream G-III-based bid for the LRAACA program.
In 'Jane's Civil and Military Upgrades 1993-94' under the Japan Aircraft Development Corporation entry it has the Kawasaki licence-built P-3C Orion. More interesting it then goes on; "for future procurement, Kawasaki has proposed a number of variants to the Japan Defence Agency including an ocean surveillance version, a military transport and a systems testbed."
Has anyone any further details?
Boeing 737-based maritime patrol aircraft proposed for Japan circa 1974.



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The BAC 1-11 ASW variant, already shown in #10:


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Came across this over on e-goat:


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From the thread;


Douglas factory desk model of the MDC DC-10 LRPA (Long Range Patrol Aircraft / Canadian Air Force).


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A couple of interior views of the 720 ASW testbed.

Cutaway of the proposed full-on 707-ASW; Bullpups underwing.

All from Flight in 1973.


Some refined data by 1974:

  • MTOW 336,000 lb. 18.000 lb of avionics and 7,700 lb of disposable stores.
  • Could also lift 28,000 lb of cargo / personnel over 3,600 nm in secondary transport role, though by 1975 the cargo door had been eliminated from the design
  • Radar had full coverage for 320 deg. azimuth and partial coverage for the remainder
  • MAD on each wing-tip
  • Dash at 520 kts, loiter at 160 kts with partial flap
  • Proposed to Canada and Australia

Other note: Germany also considering the smaller four-engined 737-ASW along with the S-3


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Digging for the 707-ASW finally revealed to me the reason that the CP-140 adopted avionics from the S-3 rather than the P-3.

Apparently Boeing's proposal had leap-frogged a generation of technology ahead of the P-3 and had oodles of internal space.

Lockheed's response was to modify their proposal to use the S-3's Univac AYK-14 computer and other systems, which freed-up a lot of volume as well as improving processing performance.

In the end the 707-ASW was rated as superior on capability and overall performance, but the P-3 won the competition on account of lower operating costs.
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