Posted on 06/14/2004 2:07:09 PM PDT by avg_freeper
WASHINGTON (Reuters) - The U.S. Navy on Monday awarded Chicago-based Boeing Co. a multibillion dollar deal to design a replacement for the Navy's fleet of submarine-hunting P-3 aircraft, congressional sources said.
(Excerpt) Read more at money.cnn.com ...
So, I'm on the first tee with him. I give him the driver. He hauls off and whacks one -- big hitter, the Lama -- long, into a ten-thousand foot crevice, right at the base of this glacier. And do you know what the Lama says? Gunga galunga. Gunga, gunga galunga.
So we finish the eighteenth and he's gonna stiff me. And I say, "Hey, Lama, hey, how about a little something, you know, for the effort, you know." And he says, "Oh, uh, there won't be any money, but when you die, on your deathbed, you will receive total consiousness." So I got that goin' for me, which is nice.
Thanks. And I'm sure it will be very "network-centric." ;-)
No. When you climb aboard and all you can smell on the bird is pi$$, vomit, hydro fluid, and kerosene, in that order, it's time to look for a new commanding officer. For several years I flew on the SP-2H, which was then 30 years old, and our aircraft were kept clean.
Right
see my #68
Sure I bitched like everybody else when I had to do all that work. But I'll tell you what! When I left the Squadron after 4 years. those aircraft still looked brand spanking new! Inside and out.
Not really, that just means you have to drag two dead weight engines with you. It only makes sense when you turn an unsuccessful airliner (Lockheed Electra) into a maritime patrol craft.
When you're talking about so many hours onboard, comfort and quiet become major factors in mission completion. Loud props, for example, cause fatigue; as does excessive vibrations. At a certain point, it makes doing the job a good bit more difficult than it has to be...remember, we might fly for 6-8 hours just to get to the mission location. Once there, of course, excessive noise will distract and confuse operators.
The aircraft is equipped with five bunks so crews can get sleep if necessary, two heads with actual FLUSH toilets (something we've never had...the most junior guy on board on a P-3 gets the duty of "emptying the bucket" If it spills, that's a horrible day.)
The aft galley has a microwave and a fridge, plus a coffee maker. P-3's have the fridge and coffee maker, but none I've ever seen work anymore. Some of the old ovens do, but that's rare.
Of course, most importantly, we're looking forward to trying out the mission systems. I myself am salivating over the Acoustic suite, and the RADAR will improve by a great stride as well. Plus, the cameras and IR and ESM gear will take all the leaps forward that have been put off while they waited for the ORION to finally retire.
Today, this was much the discussion around the squadrons. Some of the older salts are of course skeptical (especially the FE's...we haven't told them that their jobs are now obsolete on the 37...we're merciful that way. Unfortunately, some have notice dthat there's no FE chair in the cockpit. They've started to ask questions). Most of the younger guys are optimistic that it'll be a vast improvement.
Don't mention things like L/D and thrust-to-weight, or the fact that modern TF engines are every bit as effective and MORE efficient than any T-56 ever made. People don't want to hear that stuff...it blows their worldview.
Seriously, aircraft performance, engine performance, and aerodynamics and structures have taken at least an order of magnitude of leaps since the Electra first rolled out. Frankly, I'm surprised at all the negatives, especially from those who are involved with aviation.
>>> Frankly, I'm surprised at all the negatives, especially from those who are involved with aviation. <<<<<
Maybe it's because our eyes aren't glassed over from all the squiggle lines, flashing lights and can read thought all the Bravo Sierra they were feeding you on there demo of there vaporcraft.
Think your safer.
Now your flying along at 200 ft in weather you'd rrrr..rrr.rather na...na..not be around. You hit one of those nasty microdownbursts. The pilot " slams " those 4 ( or 2) power levers forward. Well because you need power NOW!
The P-3 engines go:
Yes sir! here ya go! Need some more? You in back go Whoo that was a big one!
The MMA 737 TF engines go:
Ah just a sec...(splash).... You in back go Aw... S**T...
The people who fly into Hurricanes. Can chose any aircraft type they want. They use P-3's
That just one thing. There are many others.
And remember Computers just dumb you down!
So, does this hurt or help Nethercutt?
Turbo props do have a lag. I don't have exact number, but it seems a TF run about 6-7 seconds to full throttle, recips props are under 3 seconds, and a turbo prop should fall in between there. However, the question shouldn't be how fast it is to 100% to how fast it can go from slow and level power setting, to a slow and rapid climb. Turbofan airliners tend to have pretty high thrust to weight ratios at low altitude since the engines have to be oversized to operate at high altitude. That is to say, 30% of available thrust on a 737 is probably more than the P-3 could produce in it's glory days.
Should also mention that 737s have big spoilers. Cary spoilers and a bit of extra thrust, then just drop the spoilers when you need to climb. Instant gratification.
BTW, there probably are good reasons the A-10 didn't use turboprops.
The reps were more than happy to get input from anyone they could, and talk about the gear we'd be getting. Also, the locations of the stores dispensers were laid out, as were the locations of observer seats, galley, etc.
Only thing they still weren't sure of was the bomb bay. Apparently, they still had some structural things to noodle out before they could build one into a 737 airframe.
They want to make a clean leap of technology with the RADAR, sensors, and Acoustic gear, instead of just tinkering with the old stuff like before. I fully agree with that.
We've learned a lot about military birds in the past half-century. Previously, they were thought to only last a few years before replacement; after all, that's what happened with the B-17's, 29's, and others, right? Problem was, money got tighter and tighter, and we began stretching that life out to decades, to the point where it just couldn't be stretched further. Now, since we know that's the way it is now, I'm sure that we're building them to that standard, vs. the old.
An interesting question...if we had simply replaced the P-3 and other old birds when originally intended, after about a decade or so, and continued to advance at that pace, instead of patching them together for 40 years with spit and bailin' wire and then spending major $$$ for brand-new aircraft, would it have cost MORE or LESS than the way we actually did it?
Or the S-3, for that matter, which used the same engines as the A-10.
It's important to remember that, on a turbo like a P-3, the "instant response" so bandied about comes NOT from the engine being able to spool up fast, but from the fact that the thrust produced is caused by the prop BLADE ANGLE. The engines themselves only have two settings...high and low RPM. The power levers control prop pitch. Changing that pitch changes thrust.
Rockpile, I just did a quick bit of net research for curiosity.
A Lockheed Electra weighed in at 117K lbs. A 737-800 (close to the MMA) has a GTOW of 172K lbs (http://www.b737.org.uk/history.htm#737-900).
The static thrust of the 737 engines are up to 24K lbs per side, 48K lbs total. A T-56 is somewhere around 4000 shp. Figure about 80% of that gets through the prop and installation..and with 4 of them a p-3 probably puts out about 13,000 thrust hp. Converting hp to thrust is a bit weird, but if you assume 300 mph at sealevel at full tilt (and that is a guess)..a P-3 would need about 16000 thrust.
So, T/W ratios are .33 for the 737 and about .14 for the P-3/Electra. NOW, the important thing here is rate of climb which is proportional to both T/W and L/D..so you can multiply those two to come up with a direct comparison (without actually calculating ft/min ROC)
A P-3 would be lucky to pull an L/D of 15, and a 737 should easily peg 18. So our generic climb parameter ends up being 5.94 for the 737, and 2.06 for the P-3. Basically the 737 only needs .33% thrust to match the P-3 ROC.
From this, it wouldn't be surprising that the 737 would outperform the P-3 in a micro burst situation. It is good question, and needs to be verified
And I could be wrong, however, it seems this purchase may not have been aerospace welfare.
Blade changes probably aren't instant either, I'd guess 2 seconds from fine to course.
Got Hay to make today so I don't have time to respond to everything now. And may be burnt tonight.
But here ( from memory and it's been 20 + years ) are the numbers on a P-3 engine
The turbine makes 10,000 hp
6000 are used to turn the compressor on the ground
40 in the gear box
so 4600 hp gets into the prop in flight
And there's 500 lb. of thrust at full power.
JFOI
And the lag time is so short power is there Right Now! Not so with a pure jet. You have a life time of delay. ( same with a turbo charged recip. if you let RPM's fall) And this has made more than one jet buy the farm.
5000lbs thrust would be about right.
Pukin dog, would you deploy spoilers and keep the engines spooled up on a 777 if you were to be low and slow? Seems like that would take care of the spool up argument.
Also, isn't flight idle on most HB turbofans about 20% thrust?
Does 16K thp sound about right for sl static? That would assume %85 prop eff.
Jet type thrust from the tailpipe. Not the thrust from the prop.
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