LoonyBob

8 hours ago, johnm said:

On the subject of P47’s and WW2

 

Reading my last book ……… the Luftwaffe did not have much access to metals such as nickel so their max boost (super or turbo ?) for the ME 109 and FW 190 was say 18000 ft where as the P47 & P51 was something like + 24000 ft

 

The height at which the B17 flying fortress flew at - + 24000 ft

 

A distinct advantage to the allies and their bombing campaign in Europe. A distinct disadvantage to Luftwaffe pilots who had to get up to the B17 height

 

Not something well considered by many ? – these crude technical comments are made for discussion !

The DB601 & 605 used a fluid coupling for their superchargers, and varied the compressor speed by adjusting the fluid level on the fly... the max boost was limited only by the design & "trim" of the compressors. As Nev says, superchargers care not about heat.

To my mind, the JUMO 004 using hollow turbine blades welded from arcs of tubular steel was a more significant indicator of the lack of superalloys...

Mittagong - Crookwell - Rylstone, then wherever. Landable all the way, if you don't go north of Wedderburn or The Oaks... I don't much like the hop over Brooklyn Bridge to Warnervale, even if you make it over the golf clubs of Greater Sydney...

2 hours ago, facthunter said:

Turbo Chargers don't have Ball bearings . They usually just run in metal and at very high speeds. Cook them and the oilways carbon up

The very early ones used rolling element bearings, as did Whittle, and far too many WW2-era piston engines; I'd think it probably the Corncob turbine did too. Smaller turbos certainly used plain bearings post-WW2, until McInnes invented his clever floating bush (late '60s? early '70s? of course it took a while to get universal...). I'd expect any form of bearing to coke up from heatsoak, in a turbo...

I hear youse bragging about jets, but they too get sparkplug problems! Well, some of them...

They walked away, more or less!

Isn't that the way the Code Napoleon works? Guily until proven innocent? maybe I lack Gallic Insouciance...

Good point, but a pilot can be nice to them... the Super Connie engines had the exhaust turbines geared back to the crankshaft - it's called a Compound engine, wherein two or more stages of expansion are compounded to extract the power - and the supercharger ditto.

All the pilot has to do is limit the manifold pressure on takeoff. The larger problem with that engine is aggressive leaning; they ran them so lean the EGTs dropped, with the side effect of eating plugs, valves, and turbines (they used to watch every plug's voltage spike on a CRO in flight, and note the failed plugs to have them changed during refeulling...).

DAMEs - and the AMA - tend to be pretty conservative; without appropriate legislative guidelines, they tend to say "no"... aside from the legendary Helsinki Study, statistical analysis of the regulation of medical conditions is scanty, and based upon poor sample sizes.

Wanna crowdfund an exhaustive literature search and analysis of probabilities, to determine levels of safety in ICAO terms?

11 hours ago, BrendAn said:

of course there would no science involved in building 60 reactors would there.

there are thousands of stupid people involved in these projects.  

😂 Politicians decide where the public funding goes. Please name all Aussie federal politicians since Federation (barry Jones) to hold a science degree? (Barry jones).

Of course the challenges involved in designing and building a functional and "as safe sa practicable" reactor attract some of the best and brightest. That does not mean that they question the fundamental presumptions; they are modelling in atheir own respective closed systems. How long before the known negatives of asbestos, found by science, were accepted by Politicians? And how much longer, by James Hardy?

Were the people responsible for the Manhattan Project stupid, or poor scientists? I think not; yet was their achievement an unmixed blessing? Ask the Downwinders...

Simplistic logical fallacies do not help the debate.  Argumentum ad Populum is a logicasl fallacy.

3 hours ago, BrendAn said:

so they don't need thousands of meters of copper wiring .

Most elevated distribution cables use aluminium, which is widely available in mud...

2 minutes ago, BrendAn said:

you would think 17 countries building nuclear to save emissions would be a hint for australia.

Peer pressure, eh? I prefer the science, the whole science, and nothing but the science...

3 hours ago, danny_galaga said:

I'm not talking about WAS. I'm talking about IS.  All those war birds you see at air shows that run turbo chargers, surely it couldn't be the original? 

The pilots are very careful to keep the TIT down... when's the last time anyone heard a restored as original warbird on full boost?

57 minutes ago, spacesailor said:

It is a pity they can't be used for  building trusses or spars . 

OR , anything! .

It would be better than the present day. " Burials " . 

spacesailor

They are designed by FEM, to optimise their "Hgh-Cycle Fatigue Life"; and for optimum aerodynamic twist. As they are retired from fatigue issues, they are only useable in a non-fatigue environment, such as a compression member on a bridge. However, they are entirely the wrong shape for that - squat and cylindrical is the go!

Perhaps they could be chewed up and used as filler for composite beams... but the work on non-cementitious cements (I kid you not!) by Wagner makes that less economically attractive...

Not good news, really.

13 minutes ago, skippydiesel said:

I imagine that there is a significant difference between war time/win at any cost, which means wringing the last fraction of performance from an aircraft engine without concern for its service life  compared with piece time looking for a safe/reliable durable engine run at moderate power.

What kind of negative thinking is this? Have a gander at the below "aircraft" donk...

The original 95:10 weight limit of 400lb MTOW was judged to be the maximum weight that would not retain velocity on passing through a tiled roof... this is a great precedent for an energy argument, which the heavy Vehicle license equivalent ties into. If it is deemed an acceptable risk to the public to drive a road-train full of petrol, then an aeroplane having a kinetic energy euivalent to the total energy of said truck is also acceptable, with the same level of training and medical. Sorry, shouldn't use logic...

I wonder if CASA have yet acknowledged that "General Aviation" is no longer a pool of reserve pilots for the RAF in event of WW2 breaking out?

7 minutes ago, spacesailor said:

During that WAR a new,  'Aircraft / Pilot , ' had , 

In the " battle of Britain " 6 yes, SIX, ' MINUTES ' to Live .

Did that turbo have a chance to get to TBO ! .

spacesailor

I know the average life of a Spit was ~37hrs, and 5~7hrs during the BoB. 6 minutes combat?

The Lancaster (Manchester) requirement was supposed to specify a 30-hour life; the B-24 had a - yes - 24hr designed life, which meant most of them were timex after the ferry flight to the UK.

"8  Establishment of CASA

             (1)  An authority called the Civil Aviation Safety Authority is established by this subsection.

             (2)  CASA:

                     (a)  is a body corporate with perpetual succession;

                     (b)  shall have a seal; and

                     (c)  may sue and be sued in its corporate name."

The part I have bolded is the reason CASA is grossly reluctant to expose itself to any risk. This clause is unique to Australia, and was introduced under Keating as part of NeoLiberalism (2.0) disguised as economic rationalism. It is questionable whether Australia should retain its authority as an ICAO signatory, when its Aviation Authority is nobbled...

4 hours ago, turboplanner said:

Self Administering Bodies administer and automatically assume the legal responsibility. If an Entity tells them how to administer or what to administer, the liability shifts to that Entity.

"9  CASA’s functions

             (1)  CASA has the function of conducting the safety regulation of the following, in accordance with this Act and the regulations:

                     (a)  civil air operations in Australian territory;"

CASA are responsible under the Act, full stop.

Dunno about the P47, but the Piper twins use John Deere parts, washed through a heightened QC process. I did a few APMAs for parts, yonks ago.

Britten blended a leading double-arm linkage suspension, which gave phenomenal cornering speeds and outstanding braking, with a composite frame and an engine of his own design. A generation ahead of anything else on two wheels...

11 minutes ago, spacesailor said:

AGAIN " A I "

Super sized carbon BLADES .  ( As in " wind-turbine).

I Did reread it  & missed that changed word  ! .

Or , did it change ' after ' posting.

spacesailor

PS triple proof reading , before hitting button, 

 

Oh, them thangs... yer missed the word "economically". A process about as complex as oil refining is needed to discombobulate the aged resin without poisoning the scenery, as Nev mentions; but it can certainly be done. Are all the industrial chemists on holidays?

A brute force approabing,  is to oxidise the monsters at elevated temperature, which separates the matrix (resin) from the carbon fibre, but is likely to atrophy said carbon fibre. If done in a "bomb", said gases can then be scrubbed*, hydrolysed, and alkylated, or otherwise molested into a useful form. There WILL be an energy cost...

*Nope, dunno what form of scrubbing, would have to study the chemistry closely...

6 minutes ago, spacesailor said:

BUT ( JUST TO THROW A SPANNER ) .

Have they found a way to Recycle those ' super sized ' carbon plates.  

YET.

spacesailor

Just burn 'em, then extraxt the carbon from the smoke...

7 hours ago, skippydiesel said:

 I haven't really been involved in certified aircraft for about 15 years so got no idea - my intersted & I suggest, that of most small aircraft owners is how reliable (safe & minimal down time) is it and how much will it cost me to operate. 

 

As for your earlier comment - "Ahem. For a Certified engine, TBO refers to the core; "tops" are just an incidental." - The industry can come up with whatever convention it may wish (to justify a poor product) however I don't accept  that a routine (ie expected/scheduled) substantial rebuild (starting from the core) can be considered anything less than a partial/total recondition. If an engine model is subject to this level of pre TBO intervention it is not making the manufacturer's claimed TBO.

 

 

 

From the Chicago Convention of 1922 to the Chicago Convention of 1944, it was hammered out that Airworthiness is defined in terms of "Acceptable Probability of Failure", and that Airworthiness is achieved by: Control of Design; Control of Manufacture; Control of Maintenance; Control of Operations; and Control of Training.

Your argument is economic; your position is that you bought the engine, you don't want to spend significant money on it until the TBO is reached. Bad luck; the engines for London Buses were designed that way; but that is NOT how safety is achieved in aircraft that are light enough to fly.

It boils down to the physics of flight; there would be no turboprops if empty weight / MTOW ratio were not the penultimate expression of aircraft effectiveness....

What about emulating the Pentagon's emergency energy storage? We've got better composite technology now...

To be fair, Continental and Franklin also have a good weight of SBs...

5 minutes ago, spacesailor said:

ONE QUESTION ! .

To the people who Want ' solar on every roof ' .

You should kick the government in the arse. 

The houses that will supply the biggest percentage of power to the ' grid  ' ,

Are locked out of the " subsidies scene " by the $ 250 monthly power bill cap.

When we don't use All the power, it Will feed the grid .

From 3 Kw usage to 6 Kw grid feed in .

The roof is large enough that a 9 Kw system  could fit easily .

But no subsidies available. 

spacesailor

plus a dozen more locked out in this one street .

 

 

 

 

We live in an Oligarchy... Google "State Capture".