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View Full Version : Pilatus PC21, as fast or faster than WW2 fighters ?


stilton
24th Aug 2016, 04:09
Looking at some of the advertised numbers for this impressive aircraft I can see Pilatus claiming a 469 KT Tas cruise 'at altitude' and .72 Mach.


Along with a 370 Knot Vmo this performance appears better than even the P51 ?

212man
24th Aug 2016, 08:38
Along with a 370 Knot Vmo this performance appears better than even the P51 ?

Shouldn't be a surprise as similar weight and power, but with modern aerodynamics and propeller.

ORAC
24th Aug 2016, 08:53
Focke-Wulf Ta 152 (https://en.wikipedia.org/wiki/Focke-Wulf_Ta_152#Specifications_.28Ta_152_H-1.29)

That's ignoring the Me-262 and Meteor of course.

Ken Scott
24th Aug 2016, 14:26
Back in the 80s I recall having a conversation with the then DT defence correspondent, Air Cdre Cooper, in which he said that the performance of the Tucano then being introduced was similar to that of the Mk II Spitfire, so that in terms of speed what was once a fighter was now a basic trainer. I didn't check his claim particularly rigorously but I seem to recall they weren't too far apart.

PAX_Britannica
24th Aug 2016, 15:01
Focke-Wulf Ta 152 (https://en.wikipedia.org/wiki/Focke-Wulf_Ta_152#Specifications_.28Ta_152_H-1.29)

That's ignoring the Me-262 and Meteor of course.

A few late WW2 prop designs could fly faster than 370kt in level flight: Bf109K, P51D, Griffon Spitfires, Bearcat, Tigercat, Hornet, DO335, Sea Fury,...

About the aerodynamics - it would be interesing to compare the Mmo's. IIRC about 0.86 for spitfire and 262 before bits started falling off.

Evalu8ter
24th Aug 2016, 19:22
Ken,
Tucano VNE is 300kts IAS, max LL was about 270Kts (a few knots more if you turned the aircon off...). 300kts is about 345 mph, pretty well between the max speed of the Hurricane and early Spitfire. IIRC 1151 EShp (Garrett TP351) and approx 2000Kg plays 1175 hp (Merlin XII) and 2800 Kg fully loaded. Looks pretty comparable to me - and great fun as a 23 year old to be let loose in one.....

ACW418
24th Aug 2016, 19:41
How did the JP3 and particularly the JP4 compare. I seem to remember being told they were similar to early Spitfire and Hurricanes.

ACW

Wander00
24th Aug 2016, 21:34
ACW - had a similar thought

ShyTorque
24th Aug 2016, 21:51
During my basic jet training (almost forty years ago) I had an interesting conversation with Ray Hannah who had just finished beating up the airfield in the Rolls Royce owned Spitfire (can't recall which mark it was). He reckoned my JP would have him for top speed but he would get me in the turns.

oldmansquipper
25th Aug 2016, 10:36
Just before I retired from my job with at an unnamed manufacturer and purveyor of gentleman's explosive seating, I The PC21 was being offered as a general across the board replacement (from Tucano type basic to Hawk advanced) trainer on the basis of its wide performance band. The spec of the proposed chair was to be capable of coping with that, IIRC.

Madbob
26th Aug 2016, 10:12
I did my BFT at Linton in 1979/80. ISTR that the low level nevex's (500' MSD solo and 250' MSD dual) were planned at 240 kts in the JP3 and 300 kts in the JP5.


There was a slight margin in performance to catch up time, 250-260 kts was about flat out in a 3 and 330kts was possible in a 5. With full tip tanks you got a hour at LL in a 3 and 600lbs left downwind after a run in and break. In the 5 you might struggle to get to 50 minutes before fuel became an issue.....


Good training for learning to be fuel conscious! The Hawk had much longer legs and fuel (or lack of it) was rarely an issue.


These figures are from memory so may be out by a few knots but there're in the right ball park to compare them with the performance of a Hurricane or Spitfire in early WWII.


MB


PS


The Mk5A JP could mix-it ;) with the A10's quite well - and in 1980 the A10's considered 1000' MSD to be low level for the USAFE....they were quite easy to spot and the lead was usually being flown by a nugget with the wingman being the IP showing the lead pilot the lie of the land. (There being no two-seat A10's.)

PPS
VNE for the JP3 was 350 kts and 400 kts for the JP5.

Fortissimo
26th Aug 2016, 11:20
When the competition was being run for the JP replacement, a certain large manufacturer in Lancashire worked with an ex-QFI retired 2* as its consultant when developing their proposal. As airframe and especially engine efficiency had advanced a tad since the JP1, things were clearly going to be a bit easier when it came to meeting the spec. JP and Vampire T11 both side-by-side, so let's go with that. And we can do an hour on half the fuel, so let's halve the fuel capacity! :ugh:


As others have noted, PC9 was a clear winner apart from the unfortunate part about it not coming from Brazil.

Roland Pulfrew
26th Aug 2016, 13:12
As others have noted, PC9 was a clear winner apart from the unfortunate part about it not coming from Brazil.

Just before the obvious winner being announced, at a secret training base in Yorkshire (the nicer one of the 3) I remember an ex-JP QFI, now working for one of the companies bidding to replace the JP, meeting up with a mate flying a JP5 over the Vale and doing a flypast and RIAB at said base. Seeing the PC9 and JP5 in close formation (JP5 leading) was quite impressive. After the PC9 had departed back to (was it?) Brough, a tannoy went round the station asking that if anyone had taken photographs of the flypast to bring their undeveloped film (remember that?) to the CI for safe keeping. Seems we were touchy about endorsing products even back then.

LOMCEVAK
26th Aug 2016, 13:51
The Pilatus brochure states a maximum level flight speed of 323 KTAS at sea level with the highest value at 10 000 ft (337 KTAS). P-51D Vne is 505 mph. The Spitfire reached 0.92M in a dive during testing in WWII from Farnborough.

desk wizard
26th Aug 2016, 14:44
and then the prop fell off

Wander00
26th Aug 2016, 14:49
But didn't the prop come off the Spitfire

BEagle
27th Aug 2016, 08:16
I was at RAFC and then at Leeming when some bright spark invented the idea of 300KIAS LL Nav in the JP5. It bounced around in turbulence, the controls were heavier, it drank fuel, it quickly lost speed in a 60°AoB turn - and if you applied the normal technique for making good a late time at a turning point, you exceeded max continuous limits.

OK, it was fun - but what a waste of time and little training benefit over normal 240KIAS / 250ft LL nav.

A-10s flying at low level would obligingly announce themselves on UHF on the rent-a-bounce frequency, otherwise know as 'low level common'... Shortly after GW1, on one fine day I even had a go at a pair in the Vale of Evesham in a Bulldog - they honoured the threat and after a counter, went on their way. "Were you over there?", I asked. "Sure was - an' you?" came the reply - "Yes, but not in one of these things!", was my response.

Once TWU trained, it doesn't take much for the horns to come out...:E

Just This Once...
27th Aug 2016, 14:55
The JP5/5As at Finningley managed to run around happily at 300kts+ day-in, day-out. Tips helped with the fuel though. Controls were reasonably stiff at 400kts....even with a good 2-hand grip.

Pontius Navigator
29th Aug 2016, 17:31
IIRC we did 325 in the Meteor 14 at low level and 0.69/390. Not absolutely sure about that low level speed but great fun if you kept up with the aircraft.

chevvron
1st Sep 2016, 06:52
Ken,
Tucano VNE is 300kts IAS, max LL was about 270Kts (a few knots more if you turned the aircon off...). 300kts is about 345 mph, pretty well between the max speed of the Hurricane and early Spitfire. IIRC 1151 EShp (Garrett TP351) and approx 2000Kg plays 1175 hp (Merlin XII) and 2800 Kg fully loaded. Looks pretty comparable to me - and great fun as a 23 year old to be let loose in one.....
I remember chatting to Desmond Norman who was trying to 'sell' the Firecracker to the RAAF at Fairoaks the time. He told me ruefully that in order to get 250kt ias at low level, the Tucano had to be re-engined and hence almost re-designed whereas his aircraft almost made it in its original form.
The Firecracker by the way, was operating easily from the 813m runway at Fairoaks as could a Spitfire or Hurricane; could an RAF Tucano do that?

Davef68
1st Sep 2016, 07:38
As others have noted, PC9 was a clear winner apart from the unfortunate part about it not coming from Brazil.

Or more relevant perhaps, not being built in Belfast

Lingo Dan
2nd Sep 2016, 11:24
What was "normal procedure" for making good a late time at a turning point? My experience on the JP was in 1970 :)

Madbob
2nd Sep 2016, 17:20
LingoDan


The time tolerances we worked to in say a Final Nav Test ISTR +/- 6 seconds all using Mk1 eyeball, stopwatch, compass and map (1:50,000 for the IP to target).


There were two options to catch up time; the first obviously was to cut the corner at a turning point or more scientifically, say if say 30 seconds late when planning to have a ground speed of 300 kts, i.e. 5 miles a minute, to increase speed. 30 seconds late meant that you had 2.5 miles to catch up.




How much and how long depended on how long you had left to the target but say it was 10 minutes away, then you could increase speed by 30 knots (an extra 1/2 mile per minute) for 5 minutes to get back the lost time and then revert to the planned speed after allowing for the higher headwind. If you were early due to a tailwind then the amount you had to slow down by could be worked out in the same way.


Obviously the JP only had a limited margin to increase speed so this wouldn't allow for major deviations from plan but you still were expected to try!


I hope that this makes sense - it was over 35 years ago and way before GPS!


MB