Stratojet Albatross

Helldiver:

Although a jet engine is not a vacuum, nor is a sail boat an airplane, And despite toiling away for 20+ years as an AME, with several thousend hours of flyingboat and amphibian maintenance and operating hours, thousends of hours developing and fabricaring advanced floats, and growing up on boats of all sorts, I would not presume to debate you. As for covering up inlets, and the far out things happening at high power settings in inlets, look at what MiG and Sir Siddney had to do with the MiG29 and Harrier, respectivly, to get them to breathe with a mesh FOD screen in front of the inlet(MiG), and at max power/zero airspeed with out intolerable airflow sparation(Harrier). Aye, theres the rub. jet engines do not like disturbed airflow at the compressor face. Ask the guys at GD about the 10,000 screaming agonies suffered trying to make the F-111's inlets behave( ducts too short, unfavorable flow interaction from the glove) Massive computing power to run computational fluid dynamics have helped, But there is a reason that no one has tried to make jets breath backwards, or cover up inlets, out side of a few 'stealth' applications, which dont suck backwards, and suffer from pressure recovery penalties from screens and baffles, which is why the second generation LO aircraft use carefully designed longish 'S'ducts and lots of RAM.
But what do I know.
Cheers. 3/7charlie
 
While I recognize your work and experience over the years, I don't think that your quite up to snuff on fluid dynamics.
A wing is a wing whether it's on a sailboat, a hang glider, a sail plane, a bi-plane or a monoplane. They all work the same at different velocities.
As far as the F-111 is concerned (I worked on the prototype) your talking about a different, high performance, jet engine with a completely different demands and purpose. They were faced with making it's cross section as small as possible in order to reduce it's radar signature. (they never won)
The demands made on an amphibian, with a lot lower power requirements, are quite a bit different. You can look at the Lockheed 1011 with a 17 foot drop until it meets the engines inlet.
 
Like I said, Helldiver. I could not presume to debate any one who has done everything, I bow to the mighty weight of your wisdom, Sir, as allways you are right about everthing. Of course, sail boats and vacuum cleaners are precisely like aircraft. Age=wisdom. How could I forget. I am also confused, as LO was not considered in the F-111. If you can look down the inlet and see the fan, so can any radar system, and the inlet(compressor face) and, unsuprisingly, front bulkhead(behind the radome) and cockpit are the big contributors to RCS.
Al Webbers LHA may be found at FS Shipyards, Pay ware, but inexpensive,and you get a nice AAV-7. The repaints look great.I cant wait.By the way, does anyone know what it is on the panel the causes a crash to desktop when the 2-D panel is selected?(running in FSX)
Hanging my empty head in shamed ignorance-3/7charlie
 
does anyone know what it is on the panel the causes a crash to desktop
Click to expand...

I am running this in FSX. Have had a error message and it seems to have stopped due to my omitting to add the ground callouts into the main Sound folder. You can switch the callouts on/off on the panel. The d/l also says you need the gaugesound.dll in the main FS9 (FSX too?) folder so I did that too.

Re FSX, I have also had to raise the float contact points as it sat too low in the water but then I found the nose wheel brake sprayed sparks etc on land so I have found a compromise in the contatct points that works. Will keep tweeking and report any other anomolies/fixes.

expat
 
Helldiver definately has the right - and a good - idea re the need for some water ingestion protection. I also thought your artwork mods to the screenshot are very well done, Helldiver.

I am not a aerospace engineer but recall that the Seamaster had all sorts of problems in this regard. At the same time I have never seen a reverse facing intake on a jet engine. The L1011 (and 727) had a long ducted intake, but that remained the same diameter as the fan and the intake was still forward facing to benefit from the "ram" effect.

It may be that in order not to constrain the airflow into the compressor that a reverse facing intake needs to have the constant diameter of the engine fan. Kind of in the shape of a donut cut in half. The resulting drag coefficient would likely be negative however.

I also don't know whether having air coming into the intake against the slipstream and also so close to the opposite - and stronger - flow out the back of the turbine nozzle would have adverse effects.

Back to the original topic - those paints on the first couple pages look great and I hope they get released. Having done a civil version, this one is made for a USMC "special ops" version - maybe like the CS C-130 Herc that comes with a very cool low vis USMC paint, if you are familiar with that model.

expat
 
If my memory serves, the P6M's were fairly free of water injestion. As in the test video, jets can swallow alot of water, dirt ect, as long as its free from big, hard chunks. The 2 XP6M's and YP6M-1's suffered from being short on puff(J-71's), and so had afterburners fitted to speed things up on take off, however, the A/B were unreliable and would blow out on take off, and required the full time attention of the co-joe to keep the fires lit, which, according to several of the pilots , resulted in a very high workload in take off. The proximity of #2 and 3 jet pipes to the hull also caused acoustic and thermal cracking and damage to the skins and structure of the hull, so T/O proceedure was altered to useing A/B in the out board engines (1&4) only. The P6M-2 were fitted with J-75 P-2's, with out A/B, with the engines toed out and stagger removed. Loads of puff. A more serious problem for a turbine or jet powerd boat or seaplane, and,indeed, any gas turbine opperating at sea or in dusty(Smokey) conditions is salt or dirt building up on the compressor, reducing efficancy and reducing power. The solution is a fresh water compressor wash, literaly spraying water down the inlet while running, and washing the compressor off. In the Seadart, Convair engineers installed a 30 gal or so tank of water so you could hit the switch before shutdown and 'hose it out'. Carefull placement of strakes and fences, and a bleed air system work very well with out penalizing engine performance in ALL flight regimes. The Shinmewa US-1 uses bleed air and a very deep slot behind a large fence on the chine to direct spray behind the props.Coupled with a dedicated T-53 driven compressor/APU in the hump aft of the wing to supply lots of air with out robbing the flight engines, and blowing every flying surface on the aircraft , the aircraft can fly off in seastates that woud give alot of respectable sized vessels a blender ride.
Or the 737-200A dirt field kit, a defflector on the nose wheel, and a probe at the 6 'o clock position on the inlet that uses bleed air to trigger a vortice that 'sweeps' dirt, stones ,water and gophers out of the way of the inlet. PT-6's use an ice vane, a moveable slat in the bottom of the inlet to position the boundry layer in a fashion that separates the crud and dumps it out the spill door. Lots of helios and turboshafts have screens and filters and ice shields and vortice particle separators, but run at much lower mass flows than turbojets or turbofans, and all will take a performance hit, so great care is taken to ensure unobstructed flow. I saw an AT-802 once that got is plenum filters plugged solid from a combination of lots of water and lots of dirt( it uses a pair of K&N truck air filters) and a broken aux air door. It collapsed the plenum box and cowling like a beer tin, and the compressor stall and massive instant overtemp blew the T-wheel out the stacks. Impressive.
I am waitng as well, as the SJ Albert has been crying for some Mil paint. I was supprised that Sean Doran didn't do one of his cool unmarked cammo schemes for it, like the ones he did for Mr.Heyarts PZL Steam Otter. Got that one to go in FSX, and its one of my favorite Spec-Ops platforms.I'll have to get my thumb out and finnish up a paint pak for the P6M-2 and P5M.
Cheers 3/7charlie
 
3/7charlie said:
But there is a reason that no one has tried to make jets breath backwards
Click to expand...

Not to attempt to reignite any debate or anything, just to sling in a bit of an oar...

I believe that the Bristol Centaurus that was modified for the Bristol Brabazon had some sort of reverse intake system incorporating multiple s-bends into the intake, so it can probably be done, with a lot of thought. The exact details are hazy, just a memory of seeing the engine on a stand in a museum (possibly Cosford of Duxford?)

M

BTW an extremely nice looking model, even sort of fits with my slowly expanding 1960-1980 sim.
 
Most all piston(raidial) engine have the carb on the backof the case and some pretty involved ducting. The Bristol Proteus turboprop had a notoriously labrintine inlet configuration that suffered from quite horrid iceing problems.
3/7charlie
 
Hey Lazerbeak, how are the repaints comming? Have'nt heard anything for a while. Still waiting for news on those!. P6M paint package should be out by morning. Check for the thread in FSX fourm.
 
SOH has had much ups and downs for a while but I wonder if Falcon has had any time to do his wonderful repaints? Smoothie are you still around? You had some wonderful repaints as well. Lazerbeak, on 5 Jul you had 4 cool repaints and by 10 Jul it was up to six really great repaints. Whats up, did we miss it? You guys are teasing us or what (smile)?!

Thanks in advance.

Ed
 
I started to get them ready for upload, but things happened, one thing led to the other thing, and it got put on hold longer than I realised. I'm still with intentions to upload, even have some other paints cooking, so now that I see there is still interest, I'll get back to work on sharing these. :)
 
All paints have just been uploaded, so you will see them soon. :)

More paints are in consideration. Including a made-up tourist plane registered in St. Maarten, and more military is planned, with a whole set based on JMSDF paints.
 
Lazerbeak,you are the man! Now I just have to decide if I should work today, or play!.
As Chairman Kojii said to Bender-"Domo arigato, mr roboto"
 
Lazerbeaks repaints are on-line, and waaaay cool! Dude, thanks. Banged em in and went for a quick spin.
Also found a disapearing contact thats been staying just out of reach off Wake.
 
I have the same question as morpheusfz, I checked here at SOH, Flightsim.com, and Simviation with no luck.:isadizzy:
 
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