Comparisons - New vs Old

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JMBIII

Recruit
8
23
Jul 31, 2014
I just ran across a photo of a 50 cal. sticking out of the wing of a Brazilian Super Tucano. That got me to thinking "how would a Super Tucano stack up against a WWII fighter'?
Super_Tucano_FN_Herstal_M3P_small.jpg
 
The AIM-9L on-board skews the comparison - the S-T can fire it from distance, as well as from any aspect. Without the missiles, the late-war fighters would've been in advantage, IMO. Early- and mid-war fighters vs. S-T - probably boils down on who was 1st to spot the enemy.
Just having two HMGs (even if those are much better than anything used in ww2) aboard the S-T might give some breathing room to the P-47 or F4U.
 
Cool comparison but just a touch of apples to oranges. For the sake of argument I will look at them from an Air to Air perspective. I'm also going guns only however the Super Tucano (A29) can carry a variety of short range air to air missiles (the P51 could easily be modified to carry the same however one has to draw the line somewhere).

The P51 has HMG, and speed advantage. It was built for WW2 "fighter duties", predominantly Air to Air after the addition of the Merlin.

The A29 has legs of similar length, more reliability and the ability to operate from austere airfields.

But cutting to the chase an Air to Air engagement would be interesting. The P51 has a climb and speed advantage while I would bet with more modern aeronautics the A29 has more docile handling, similar G limits, and a newer tech gunsight. It comes up short in ammo count but does have 1100 RPM HMGs (2) versus 6 for the Stang.

It's my opine that it would depend on the fights starting parameters. Should they be equal start nose to nose at 20k I would think the P51 would have the long term advantage as long as he didn't anchor in a slow speed fight.

Cheers,
Biff
 
RPM changes take a while with a PT6 engine, which would be a significant advantage to its piston engine adversary
 
RPM changes take a while with a PT6 engine, which would be a significant advantage to its piston engine adversary

Constant speed prop; the prop rpm is fixed. In any case, it will go flight idle to takeoff power in under eight seconds, possibly much less.
 
Constant speed prop; the prop rpm is fixed. In any case, it will go flight idle to takeoff power in under eight seconds, possibly much less.
Not that much different to a large radial (if the pilot's handling the engine properly). But, I'm not sure how much they changed the power during dogfights anyway.
 
RPM changes take a while with a PT6 engine, which would be a significant advantage to its piston engine adversary

I think big throttle changes on the V12s were handled at other than smashing against the stops (no super fast power changes) but could be wrong. However a modern turbo prop will have a FADEC (Full Authority Digital Engine Control) which usually allows for unrestricted throttle movement in all regimes (SUPER Nice to have).

Cheers,
Biff
 
I think big throttle changes on the V12s were handled at other than smashing against the stops (no super fast power changes) but could be wrong. However a modern turbo prop will have a FADEC (Full Authority Digital Engine Control) which usually allows for unrestricted throttle movement in all regimes (SUPER Nice to have).

Cheers,
Biff
Either way, idle to full throttle takes time.
 
How many aircraft in contested airspace have their throttle at idle ?
The comment was used to demonstrate the time to make power changes. Idle to full throttle numbers are the only ones available for comparison.

But, depending on the situation, flight idle may be used: e.g when descending to maximise descent rate without gaining excessive speed.
 
I think big throttle changes on the V12s were handled at other than smashing against the stops (no super fast power changes) but could be wrong. However a modern turbo prop will have a FADEC (Full Authority Digital Engine Control) which usually allows for unrestricted throttle movement in all regimes (SUPER Nice to have).

Cheers,
Biff

So did the fueldraulic and other analogue fuel controls that immediately predated DEECs
 
So did the fueldraulic and other analogue fuel controls that immediately predated DEECs

Yes but you could easily over torque a turbo prop.

The original Eagle engine, the F100-100 with Electronic Engine Control, would have blowouts, over temps, roll backs, and degraded performance over the life of the engine. The Digital EEC, AKA the DEEC, eliminates ALL of those problems, and adds much better throttle response / more thrust. It also eliminated the requirement for a hush house / engine run building.

The OV-10 had Garrett's, and the fuel control system used power and condition levers. The former acted like a throttle, while the ladder acted like a min RPM controller. It had a difficult time making min torque on a summer day but would over torque easily in the winter time.

The RC-26 had Garrett's as well, but had a different fuel control system. It was more reliable but not as user friendly as the Broncos. It would allow over torque but not over speeds if I remember correctly.

Turboprops don't like to be over torqued or oversped in the two examples I have flown.

Cheers,
Biff
 
I am a little surprised that FBW hasn't been mentioned. It enables the aircraft to be flown at the edge of the envelope at any time in any situation without suffering a dramatic departure. Whilst this may add little to the performance of the best pilots it would make a significant difference to the vast majority of average pilots.
As was once pointed out to me, if my average pilot / aircraft combination is better than your average combination, you lose.
 
So far, I've seen the focus on the engine performance comparison.
But how well would a modern COIN aircraft hold up to the actual fighting profiles of the WWII era fighters?

How well would a Tucano perform against an A6M5 or Fw190A at lower altitudes in a turning fight? Then there's the La-7, F6F, Fw190D, Spitfire IX, N1K2-J and so on.
No amount of engine power/response, modern MGs or modern gunsight will save you if your opponent knows his machine and exploits it to it's fullest.

There's a long list of COIN aircraft, but their focus is on counter-insurgency aka ground attack, close-support and pin-point strikes. Of all the types out there that *may* have a chance against a WWII era fighter, I'd say the T-6 "Texan" (retired) and the Cavalier "Mustang" would be the only ones who'd have a chance and by a twist of Irony, they're rooted in the WWII era.
 
I am a little surprised that FBW hasn't been mentioned. It enables the aircraft to be flown at the edge of the envelope at any time in any situation without suffering a dramatic departure. Whilst this may add little to the performance of the best pilots it would make a significant difference to the vast majority of average pilots.
As was once pointed out to me, if my average pilot / aircraft combination is better than your average combination, you lose.

Glider,

Currently of the COIN type aircraft none to my knowledge have FBW. It's expensive, and most of the COIN aircraft are current or established designs so no resources would be put towards more advanced flight controls.

FADECs are the engine controls that mirror FBW and allow the pilot to move the throttle without worry of engine damage.

Cheers,
Biff
 
Glider,

Currently of the COIN type aircraft none to my knowledge have FBW. It's expensive, and most of the COIN aircraft are current or established designs so no resources would be put towards more advanced flight controls.

FADECs are the engine controls that mirror FBW and allow the pilot to move the throttle without worry of engine damage.

Cheers,
Biff
Thanks for this, much appreciated
 
Just a bit of info about FADEC systems. They have several components, all working together governed by the electronic engine management computer (EECU or some other acronym). Take a look at this image of a PW100 series engine, big brother to the PT6 in the Tucano.

33938286118_e8f70b277b_b.jpg
EECU-2

The black box with the blue label on it is the Electronic Engine Control Unit (on this aircraft), it is the brain of the thing. It controls via the pilot's input the entire engine workings. At the top of the image is a circular crank assembly, that is from there where the pilot's cockpit input comes, with linkages to the mechanical fuel control unit directly below it, obscured by the top engine brace. Push rods from this go to the propeller control unit, obscured by the forward end of the engine brace and the AC geni above it. The EECU also controls torque output via the torque signal condition unit, the smaller black box to the EECU's right. It also has control over the compressor dump valve, not visible in this picture, but located at top right. On command of the EECU it opens at low to medium engine (NH - high pressure compressor) rpm to allow pressure build up in the compressor to exit, then closes it again.

In this type of aircraft the EECU works for its particular flight regime and looking at the picture below, you can see what control the pilot has over it.

33938284638_60b1c7c368_b.jpg
Engine panel

To the left of the two vertical rows of engine instruments you can see a small rotary switch named PWR MGT, for, obviously, power management. On take off, the pilot moves the power levers to an indent indicating 90 percent power and the condition levers (for propeller pitch condition, controlling the propeller pitch control unit, see above - in this aircraft the PEC, which you can see written under the rotary switch) to Max, then doesn't need to touch these again. He/she rotates the PWR MGT switch to TO, for take off, obviously and rotates it again once established in the cruise climb etc etc. This panel is from a regional airliner of the 1980s/90s vintage, so these days all this dial stuff is replaced by EFIS screens, nevertheless, the power management function through the engine control unit is the same.

Given that in a high speed two seat military trainer the parameters of operation are going to be different, the engine management system computer will be programmed differently, but the set up will be the same. As Biff pointed out, you can overspeed turbo props quite easily, even with a FADEC system on board. If you notice my earlier statement, on that particular aircraft, on take off the engines are working at 90 percent, not hundy percent, that's emergency power and prevents inadvertent engine overspeed. These aircraft are fitted with propeller overspeed governors to protect the propeller if an engine overspeed condition is reached, usually over 100 percent power. Conversely, when in Beta mode, or reverse pitch, the engine can also be oversped. Since engineers are required to test the engines at their higher parameters, this is a very real danger that pilots in airliners at any rate are unlikely to encounter as often, but there are placards in the cockpit to advise the pilots not to overspeed the engines on landing when pulling the power levers into beta mode.

Sorry, a bit off topic, but modern turbo props are a very different kettle of fish to a piston. Pure jets don't have to worry about half of this stuff!
 
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Just to add to this, the Fw 190 had an electro-mechanical engine management system called the Kommandgerat, which governed propeller pitch, mixture and boost depending on power output set by the pilot, with a button on the throttle lever to alter pitch when required.
 
To simplify things, we can look to our motor vehicles.

My 1962 Chevy Nova's accelerator pedal is connected to the carburetors by a spring-loaded linkage. The moment I step on the pedal, the linkage directly actuates the butterflies and the engine reacts accordingly. If I stomp on the pedal, all hell breaks loose, the engine's RPMs instantly increase and I start roasting the rear tires regardless of conditions.

Conversely, on my 2011 Chevy HHR, the accelerator is "fly by wire". Meaning if I step on the accelerator, the "ECM" (engine computer) takes into consideration input from various sensors and responds to the accelerator's input accordingly. It's virtually impossible to "break traction" in my HHR, because the engine's response reacts in a logical manner according to it's sensor inputs. It will accelerate quickly, but it will steadily increase the RPMs while maintaining firm traction.
 

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