Flying over square
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NZScion,
at that point you are also a bit late to have turned on the PATH (Pilot Activated Tarma Heating)
@T28,
I wasn't referring to maintenance, more what all the oil has done to you
at that point you are also a bit late to have turned on the PATH (Pilot Activated Tarma Heating)
@T28,
I wasn't referring to maintenance, more what all the oil has done to you
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From the journal "No Short Days: The Struggle to Develop the R-2800", Kimble D. McCutcheon concludes that the P&Ws R2800 has been run with 150 in Hg. Kinda makes a mockery of the only-just-oversquare figures this thread contains. On the second last page:
"Using ADI, Walker was able to coax 3800 HP from an experimental “C” engine
at manifold pressures up to 150 in Hg! This is nearly twice the power the engine was designed to produce."
Interestingly, the pilots notes for the Sea Fury indicate 9.5 lb./sq. in. Is that only 19.3" Hg, or am I missing something?...... no I remember, it's indexed at zero on the ground.
"Using ADI, Walker was able to coax 3800 HP from an experimental “C” engine
at manifold pressures up to 150 in Hg! This is nearly twice the power the engine was designed to produce."
Interestingly, the pilots notes for the Sea Fury indicate 9.5 lb./sq. in. Is that only 19.3" Hg, or am I missing something?...... no I remember, it's indexed at zero on the ground.
Last edited by osmosis; 11th Oct 2011 at 06:43.
Grandpa Aerotart
Interestingly, the pilots notes for the Sea Fury indicate 9.5 lb./sq. in. Is that only 19.3" Hg, or am I missing something?
I have no idea what 9.5 lbs/sq in equates to but if its much less than 60" Hg I will surprised.
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What does MP indicate?
What else changes when you change prop RPM?
What is the ONLY control in the cockpit that is capable of regulating engine power between 0% and 100%?
Sorry... I just couldn't help myself!!
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Chimbu,
A lot of the pommie engines measured boost as PSI above atmospheric, so at ground level on a 30 inch day 1015 Hpa 9.5 inches would equate to approx 52 inches which I think is about the limit for the sleeve valve centaurus in normal ops.
A lot of the pommie engines measured boost as PSI above atmospheric, so at ground level on a 30 inch day 1015 Hpa 9.5 inches would equate to approx 52 inches which I think is about the limit for the sleeve valve centaurus in normal ops.
Ya gotta love this forum!
Just when I am thinking, "Geez this thread has become boring as bat sh*t! Six pages of posts on operating a simple reciprocating petrol engine - time to bring out the lock"!
Then along comes a PA38 Captain who says to the Chimbu Chuckler,
"Ok smart guy, i have a few Q's for you.
1. If we have a hung start, what is the easiest way to remedy it?
2. When operating the PT6, what is the most fuel efficient stage of flight?"
OK, I've got my feet up, the top off a cold Crownie, and a bowl of beer nuts on the table beside the Jason Recliner!
Over to you Chuckles!
Dr
Just when I am thinking, "Geez this thread has become boring as bat sh*t! Six pages of posts on operating a simple reciprocating petrol engine - time to bring out the lock"!
Then along comes a PA38 Captain who says to the Chimbu Chuckler,
"Ok smart guy, i have a few Q's for you.
1. If we have a hung start, what is the easiest way to remedy it?
2. When operating the PT6, what is the most fuel efficient stage of flight?"
OK, I've got my feet up, the top off a cold Crownie, and a bowl of beer nuts on the table beside the Jason Recliner!
Over to you Chuckles!
Dr
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Why do the poms, measure boost different to the yankee method?
I think you will find, that they pretty much talk in In/Hg these days. Back in the old days the seppos used Inches, and the pommes used pounds of boost because they could.
Neither method is wrong. The way they go about it is drastically different, but if you understand what/how is being measured, then you won't have any problems.
Jas.
PS why do the pommes hide their money under the soap?
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From the journal "No Short Days: The Struggle to Develop the R-2800", Kimble D. McCutcheon concludes that the P&Ws R2800 has been run with 150 in Hg. Kinda makes a mockery of the only-just-oversquare figures this thread contains. On the second last page:
no mockery of the 'just oversquare' figures presented at all. If you recall back the early pages of the thread, it seemed agreed to keep it to normally aspirated normal engines, which we both know will never make 30" at 7000 feet.
Nice post on the P&W development tho, some links would be lovely bedtime reading
----------------------------------------------------
Dr, how could you possibly consider closing this thread?
sure the 'normal' engine has run its course of discussion, but it has naturally evolved, into round ones, tho i thought turbo/supercharging would have been would have been the logical next step, however beggars can't be choosers.
Thumbs up to most informative thread of the year Cheers
Jas......off to the fridge for a fresh green tube
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Chimu wroteGiven that 0 lb/sq in 'boost' equates to 29" Hg (atmospheric) I think yes, you're
I have no idea what 9.5 lbs/sq in equates to but if its much less than 60" Hg I will surprised.
I have no idea what 9.5 lbs/sq in equates to but if its much less than 60" Hg I will surprised.
T28D Replied
Chimbu,
A lot of the pommie engines measured boost as PSI above atmospheric, so at ground level on a 30 inch day 1015 Hpa 9.5 inches would equate to approx 52 inches which I think is about the limit for the sleeve valve centaurus in normal ops.
Chimbu,
A lot of the pommie engines measured boost as PSI above atmospheric, so at ground level on a 30 inch day 1015 Hpa 9.5 inches would equate to approx 52 inches which I think is about the limit for the sleeve valve centaurus in normal ops.
9.5 lbs/in = 19.32 + 29.92 = 49.24 inches.
Given the 52 inch limit, I conclude that we got the conversion correct.
The next obvious question has to be why do we zero the instrument on the ground? well if you do that, then you have set the QFE into the instrument, and therefore you can use 'extra' boost (for want of a better description), to get the power you want. You do not need to do any calculations based on pressure/temp etc, you just did it on the ground.
How that is corrected on a distance flight, i await the answer to.
Cheers
Jas
BOTTOMS UP GLUGG GLUGG GLUGG
Grandpa Aerotart
Hey Forkie...I didn't see that post
Pa38 'captain' - I owe you an abject apology - I only saw the second post of drivel NOT your first attempt at high humour
1/. Sit on your hands and do fcking nuffink!!!
Well that is the SOP for the RR Trent 800s I sit between at work. Highly clever aeroplane the 777. As long as it has oil pressure ya throw the fuel at it and sit back and watch it do its thing. If its really unhappy, and only after several automatic dry motoring runs and subsequent attempts at a start, it gives up and you get an EICAS prompt that says "FCK IT - I give up - do some of that clever pilot ****"...so you put the FCS back in cutoff and call the gingerbeers.
Now on all the earlier jets I have flown, F28, Bae146, Citation 580 ultra, Falcon 200 and B767 you were the brains of the operation - sorry I didn't mean YOU I meant me and the people I flew with - so you would manually select the fuel control switch to cutoff...if the engine starter was still engaged you let it keep cranking for 30 seconds or so to clear all that heat etc then interrupted the start. If the starter has already cut out you do a dry motoring run before trying again.
2/. Well...I haven't sat between PT6s for about 16 years - and before that only for about 4000hrs (DHC6/E110/DHC7)...so memory is rusty. I certainly remember ridge soaring a full Twin Otter for about 15nm one day in PNG...both engines in feather...that was pretty efficient...hell of a lot of fun too...only lost a total of about 300' in that distance - at one stage I was HIGHER than when I selected both to feather. No pax, just freight of course. Another time I did the same thing in an empty Twotter at TOPD into Moresby and glided all the way to long finals at about 1500' - prolly 30 odd nm.
You may be wondering why I wasn't dobbed in by the co-pilot for these disgraceful departures from proper and good airmanship?
Well we flew em single pilot - Banderantes too - MUCH more fun than having some killjoy, no sense of humour fkwit PA38 Captain in the RHS.
And another time I remember flying back from New Britain to Port Moresby empty at FL250 in a -300 Twotter with -34 PT6s...that was pretty damn efficient - if memory serves I was still getting 150kts TAS...I think the PT6s may have actually been MAKING fuel that day! No, seriously
You didn't ask about TPE331s so I won't bore you with flying C441s - managed to get one of those from Nadi to Cooly, upwind, one night. I thought that was pretty efficient
Over to you lad.
Pa38 'captain' - I owe you an abject apology - I only saw the second post of drivel NOT your first attempt at high humour
1/. Sit on your hands and do fcking nuffink!!!
Well that is the SOP for the RR Trent 800s I sit between at work. Highly clever aeroplane the 777. As long as it has oil pressure ya throw the fuel at it and sit back and watch it do its thing. If its really unhappy, and only after several automatic dry motoring runs and subsequent attempts at a start, it gives up and you get an EICAS prompt that says "FCK IT - I give up - do some of that clever pilot ****"...so you put the FCS back in cutoff and call the gingerbeers.
Now on all the earlier jets I have flown, F28, Bae146, Citation 580 ultra, Falcon 200 and B767 you were the brains of the operation - sorry I didn't mean YOU I meant me and the people I flew with - so you would manually select the fuel control switch to cutoff...if the engine starter was still engaged you let it keep cranking for 30 seconds or so to clear all that heat etc then interrupted the start. If the starter has already cut out you do a dry motoring run before trying again.
2/. Well...I haven't sat between PT6s for about 16 years - and before that only for about 4000hrs (DHC6/E110/DHC7)...so memory is rusty. I certainly remember ridge soaring a full Twin Otter for about 15nm one day in PNG...both engines in feather...that was pretty efficient...hell of a lot of fun too...only lost a total of about 300' in that distance - at one stage I was HIGHER than when I selected both to feather. No pax, just freight of course. Another time I did the same thing in an empty Twotter at TOPD into Moresby and glided all the way to long finals at about 1500' - prolly 30 odd nm.
You may be wondering why I wasn't dobbed in by the co-pilot for these disgraceful departures from proper and good airmanship?
Well we flew em single pilot - Banderantes too - MUCH more fun than having some killjoy, no sense of humour fkwit PA38 Captain in the RHS.
And another time I remember flying back from New Britain to Port Moresby empty at FL250 in a -300 Twotter with -34 PT6s...that was pretty damn efficient - if memory serves I was still getting 150kts TAS...I think the PT6s may have actually been MAKING fuel that day! No, seriously
You didn't ask about TPE331s so I won't bore you with flying C441s - managed to get one of those from Nadi to Cooly, upwind, one night. I thought that was pretty efficient
Over to you lad.
Now on all the earlier jets I have flown, F28, Bae146, Citation 580 ultra, Falcon 200 and B767 you were the brains of the operation - sorry I didn't mean YOU I meant me and the people I flew with
Well we flew em single pilot - Banderantes too - MUCH more fun than having some killjoy, no sense of humour fkwit PA38 Captain in the RHS.
Dr
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Dr...get a catheta! train the dog to bring ya one from the fridge, you'll never have to move, nor 'run the gauntlet' again!
Cheers
Jas
PS have you seen the other bit of muppetry that PA38 and Pukeit are involved in? at least PA38 has his head screwed on for that one!
Cheers
Jas
PS have you seen the other bit of muppetry that PA38 and Pukeit are involved in? at least PA38 has his head screwed on for that one!
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Still waiting for an analysis on my valves!
You know, under square ROP or over square LOP
And how about them maintenance bills?
Chuckles..... Back to his old form
You know, under square ROP or over square LOP
And how about them maintenance bills?
Chuckles..... Back to his old form
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oh sorry Jaba....
I've seen better valves than them!
I was refraining from posting due to my knowledge of what they should look like.
Cheers
Jas
PS answer your PM!
I've seen better valves than them!
I was refraining from posting due to my knowledge of what they should look like.
Cheers
Jas
PS answer your PM!
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What PM?
Try sending it again
BTW I see the other thread you are talking about. I will be along there shortly to help sort some sheep from goats.....along with video proof.
Some of you folk need could do with some serious education and Chimbu Chuckles has imparted much of it to me, and I am forever learning more. In this other case we went out and tested theory. We learned a heap. Hopefully you and others will too.
What I have learned is that despite a really good injection of knowledge from really clever folk, I have learned there is much more to learn, and most of it is not coming from the typical 200-300 hr instructor folk like PA38 captain.
Now back to normal viewing on engines hey.....
Try sending it again
BTW I see the other thread you are talking about. I will be along there shortly to help sort some sheep from goats.....along with video proof.
Some of you folk need could do with some serious education and Chimbu Chuckles has imparted much of it to me, and I am forever learning more. In this other case we went out and tested theory. We learned a heap. Hopefully you and others will too.
What I have learned is that despite a really good injection of knowledge from really clever folk, I have learned there is much more to learn, and most of it is not coming from the typical 200-300 hr instructor folk like PA38 captain.
Now back to normal viewing on engines hey.....
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js24zzk, with regard to the journal I mentioned, I've had my copy for a while but a quick giggle search leads to:
Piston Engines
And a reference to Centaurus engine data:
Piston Engines
And a reference to Centaurus engine data:
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At chimpmunk chuckles. Well done on your failure with using google 
.
. If you had any idea of what crap you were talking about, you would have realised that the 777 has GE90 engines on them. The only time you will find yourself between two of them is when you are wearing your skirt and handing out inflight refreshments. Faker alert!
Well done on gliding the twin otter 30NM on flight sim. If you did this in real life you would get shock cooling within 2 minutes and your boss would be giving you the bill for all 12 cracked cylinders.
Oh oh ah ah what will the chipmunk come up with next???
.
Well that is the SOP for the RR Trent 800s I sit between at work. Highly clever aeroplane the 777
Well done on gliding the twin otter 30NM on flight sim. If you did this in real life you would get shock cooling within 2 minutes and your boss would be giving you the bill for all 12 cracked cylinders
.Oh oh ah ah what will the chipmunk come up with next???