P-6M Seamaster

[gray eagle]

Interesting video on the Seamaster. Some of the commentary on this aircraft at the youtube site is worth reading as well.

 

[stiz]

never heard of his plane before, sounds a pretty darn decent aircraft! how come the navy didnt take it up? Did it loose out to subs?

 

[lazarus]

politicking, infighting, short sightedness. Here the Navy had an aircraft that could perform the B-52's strike mission, at M=.95 and nought feet, without an airbase. It could also carry an impressive load of mines, with a mission of bottling up the Soviet fleet, as well as various other conventional attack missions. The aircraft could also function as a tanker. It was programmed to operate with the 'seaplane striking force' at sea from tenders, or bases afloat, or from a submarine, from which the aircraft could be serviced and armed.
There was also a proposed Nuclear powered version, and a freighter/civil transport called the 'Sea Mistress'.
The AirForce hated it. The Big Carrier Mafia hated it. The submariners and fighter Mafia hated it.
Still, the Navy went ahead, the production P6M2 was in production, the USS Albermarle and submarine tender Guavina converted to tend it, NAS Harvey Point N.C. was commissioned as the first base, and the first squadron was forming up when the axe fell, other vested interests brown nosed the right people on the Hill and had it killed.
Really killed. the tooling was destroyed, all the P6M1 and -2 aircraft were chopped up, the drawings, research work, even photographs were torched.
All that is left is a pair of tip floats-salvaged by a martin employee for a catamaran, and a few other bits and bobs; held today at the G.L.Martin museum in Middle River MD.

Wouldn't that be a great model for FSX. There is the old Frank Elton/Bruce Fitzgerald FS2002/2004 model available, decidedly elderly; but still enormously popular judging by the number of downloads.

 

[SSI01]

It's an impressive achievement, no denying that, but this thing had to have vices or limitations. For one thing, sea state could forestall any seaplane-based strike if the water is too rough to take off from. We've got to land, too. I know the hull was designed to withstand takeoff/landing impacts and taxiing in certain sea states but there must have been a limitation imposed by that. Second - those jet engines in such close proximity to the water must have ingested an ENORMOUS quantity of salt. In a few of the taxi sequences I noted some waves actually lapping on the leading edges of the wings outboard of the engine air inlets. Wow! Even if green or blue water didn't enter the engine - those compressor blades up front must have been absolutely coated with salt. We live on an island and the salt water is at least two miles away - yet unless the air is filtered somehow, corrosion will attack any metal not otherwise protected - and that's in still air. Corrosion-resistant metals can do only so much - and if the metal is corrosion-proof, isn't there usually a weight penalty associated with that? This was fairly early on in jet engine development and AFAIK composites weren't being used at this time in compressor blades or other engine components being bathed in salt spray; how did they compensate in engine components for such close proximity to extremely corrosive salt water? Engine maintenance must have been frequent and extensive. In that case it would have joined the F-106 and SR-71 in that category of aircraft that require 20, 30, 50 or more hours of maintenance for every hour of flight.

Lazarus - you are absolutely right, I know that P6M already out there, I've got it in the (aquatic) hangar. FS9 or FSX, it would be fun to have an updated P6M as a stable-mate to the Sea Dart, P5M and RY3. The last one is only available from Virtavia in FSX so that would probably be the place. Sounds like the clean-up after program closure was conducted with genuine malice toward the aircraft and its designers.

Based on my observations and comments heard during 23 years of associating daily with the Navy, there has always been a sort of descending "pecking order" in the naval aviation community, sort of like fighter/strike/recon-ECM/replenishment/fixed-wing ASW/trainers/helos. Sorry if I got things out of order, if a pro reads this. I wonder where seaplane pilots would have fallen in this mix?

A racket? Look up Smedley D. Butler.

 

[lazarus]

Don't be conspicuously better...

...than the guy who owns the judge.
I know Butlers's story well. I always thought a whole bunch of Wall street fat cats bought their way out of the noose that time.
The P6M had some problems, certainly. One XP6M and YP6M1 were lost to horizontal stab design defects, The engines gave loads of trouble, she suffered porpoising under some conditions, and the tip floats tended to 'dig in' in turns. The naval stores of the day also often disintegrated on release due to high dynamic pressures at low altitude. The P6M-2 seemed to have the aircraft's problems licked, the magnificent J-75 was trouble free, eliminating the trouble prone afterburners, reducing take off run, eliminating porpoising, and capable of driving the aircraft to M=1 in a shallow dive at 10,000ft. The negative dihedral of the wing was eliminated, removing the float dig in. The hull and structure design was enormously strong, and water ingestion was not considered a problem, the boat could operate in 12 +ft seas, one test flight recorded a prolonged water run at over 180kts in 6 ft seas!, the ride described as 'pretty damned good!' Corrosion in jet engines is always a problem; the environment in there is already bad for corrosion/erosion, so the steel types are all ready very tough, the J-75 for the boat was marinized by substituting other alloys for materials corrosion prone, not so much of a weight penalty as one might think, and an on-board compressor wash system was installed.
The down side. 400 million had been spent, and this was played endlessly on the Hill, though the Airforce had spent a heck of a lot more on re-build programs to fix defective clamps , wing plank cracks, longeron cracks, milk bottle(wing attach) pins, cracking flaps, ect, ect; on B-52's and B-47's which were 'flying to pieces' from being driven around at 350kts on the deck, then tossing the lot in the bin a few short years later- the bulk retirements of fatigued out -52's and -47's in '62-'65; on the B-58 and XB-70 (Spectacular aircraft; yes! suited to the operational world? Maybe not so much, and still tied to long runways and heavy infrastructure.) 400 million Eisenhower bucks compares pretty well with what the Airforce was spending on single point systems that could only fight a nuclear war, and then have no bases to return to. The AF had to spend big bucks a few years latter to give their bomber fleet a worth-while conventional attack capability, and negotiate expensive and politicly dodgy basing agreements. Today, for instance, Guam is looking like a big missile beaten zone. Can't dodge, can't hide. I would not want to be there if the balloon goes up. When the balloon goes up.
A pretty good article on the 'Boat and operational doctrine. Ignore the histronics, though the author does make some good points.

http://www.combatreform.org/p6mseamaster.htm

 

[gray eagle]

...than the guy who owns the judge.
I know Butlers's story well. I always thought a whole bunch of Wall street fat cats bought their way out of the noose that time.
The P6M had some problems, certainly. One XP6M and YP6M1 were lost to horizontal stab design defects, The engines gave loads of trouble, she suffered porpoising under some conditions, and the tip floats tended to 'dig in' in turns. The naval stores of the day also often disintegrated on release due to high dynamic pressures at low altitude. The P6M-2 seemed to have the aircraft's problems licked, the magnificent J-75 was trouble free, eliminating the trouble prone afterburners, reducing take off run, eliminating porpoising, and capable of driving the aircraft to M=1 in a shallow dive at 10,000ft. The negative dihedral of the wing was eliminated, removing the float dig in. The hull and structure design was enormously strong, and water ingestion was not considered a problem, the boat could operate in 12 +ft seas, one test flight recorded a prolonged water run at over 180kts in 6 ft seas!, the ride described as 'pretty damned good!' Corrosion in jet engines is always a problem; the environment in there is already bad for corrosion/erosion, so the steel types are all ready very tough, the J-75 for the boat was marinized by substituting other alloys for materials corrosion prone, not so much of a weight penalty as one might think, and an on-board compressor wash system was installed.
The down side. 400 million had been spent, and this was played endlessly on the Hill, though the Airforce had spent a heck of a lot more on re-build programs to fix defective clamps , wing plank cracks, longeron cracks, milk bottle(wing attach) pins, cracking flaps, ect, ect; on B-52's and B-47's which were 'flying to pieces' from being driven around at 350kts on the deck, then tossing the lot in the bin a few short years later- the bulk retirements of fatigued out -52's and -47's in '62-'65; on the B-58 and XB-70 (Spectacular aircraft; yes! suited to the operational world? Maybe not so much, and still tied to long runways and heavy infrastructure.) 400 million Eisenhower bucks compares pretty well with what the Airforce was spending on single point systems that could only fight a nuclear war, and then have no bases to return to. The AF had to spend big bucks a few years latter to give their bomber fleet a worth-while conventional attack capability, and negotiate expensive and politicly dodgy basing agreements. Today, for instance, Guam is looking like a big missile beaten zone. Can't dodge, can't hide. I would not want to be there if the balloon goes up. When the balloon goes up.
A pretty good article on the 'Boat and operational doctrine. Ignore the histronics, though the author does make some good points.

http://www.combatreform.org/p6mseamaster.htm

That link ^ is packed with a lot of history and info I was unaware of. Thanks for the link.

 

[gray eagle]

P6M Bombing System

Video show how and where the bombs were loaded. Very clever.

 

[lazarus]

Also note that the weapons bay can be accessed from 2 long hatches aft of the wing box top sides, allowing re-arming afloat. The rotary bomb door was described as one of the great designs of all time, giving a clean release throughout the aircraft's weapons delivery envelope; though a great deal of effort went into the seal design, the XP6M frequently suffered from a flooded 'mine bay', obliging the aircraft to draw some 11ft of water. martin went to great pains to design an aircraft that could be maintained and serviced afloat- almost all maintenance functions could be conducted from the top side of the aircraft afloat(even engines could be changed afloat), or from specialist BuDocks designed 'drydock' maintenance platforms. Too heavy to hoist aboard, the navy designed a deployable single aircraft floodable dock for getting the aircraft out of the water, and a retractable ramp/cradle fitted to the Albermarle for hauling the Seamasters and Tradewinds aboard. A similar system was designed for LSD's.
On a sim related note, I have been modeling seaplane stuff- large ramped barges(like the ones convair used to support the R3Y), various seadocks, work boats; and made a start on USS Pine Island;with an eye to the converted Albermarle. I see a P6M thread in the FSX forum, so more news there.
An amazing machine.

 

[gray eagle]

Also note that the weapons bay can be accessed from 2 long hatches aft of the wing box top sides, allowing re-arming afloat. The rotary bomb door was described as one of the great designs of all time, giving a clean release throughout the aircraft's weapons delivery envelope; though a great deal of effort went into the seal design, the XP6M frequently suffered from a flooded 'mine bay', obliging the aircraft to draw some 11ft of water. martin went to great pains to design an aircraft that could be maintained and serviced afloat- almost all maintenance functions could be conducted from the top side of the aircraft afloat(even engines could be changed afloat), or from specialist BuDocks designed 'drydock' maintenance platforms. Too heavy to hoist aboard, the navy designed a deployable single aircraft floodable dock for getting the aircraft out of the water, and a retractable ramp/cradle fitted to the Albermarle for hauling the Seamasters and Tradewinds aboard. A similar system was designed for LSD's.
On a sim related note, I have been modeling seaplane stuff- large ramped barges(like the ones convair used to support the R3Y), various seadocks, work boats; and made a start on USS Pine Island;with an eye to the converted Albermarle. I see a P6M thread in the FSX forum, so more news there.
An amazing machine.

A video to support some of your comments:

 

[gray eagle]

More info on the amazing P6