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Dominator2
10th Aug 2017, 08:21
iRaven We also have the Phenom which I understand has an issue with Cranwell's runway length if it uses the anti-icing system and wants to fly close to MAUM

I was interested to see this quote in a different thread. We operated the Dominie from CWL for years when often we had to operate with reduced MTOW. Whenever in icing condition our fuel uplift was reduced by up to 2000lbs. Obviously, whenever the temperature rose above 21deg C we also suffered. Flights into Europe with greater extremes in temperature were often challenging.

The worst part was that we were using 1950s techniques to calculate ac performance. The ac was often on a knife edge after rotate and the numbers calculated may have been way in error.

We tried to purchase a modern software package, however, HQ22 Gp would not fund the few thousand required.

At least I assume that Phenom has been procured with full perf data and a software package to enable accurate perf calculations?

camelspyyder
10th Aug 2017, 14:57
Of course if you were really lucky, your retard PA would overfuel it by 600lbs. See how it climbed then!

Luckily, this was at a sea-level locale with a bit more concrete than at home-plate.

Dominator2
10th Aug 2017, 15:20
The last person that I knew who overfilled a Dom was a pilot plus 5 taking off from in island in the Med with the OAT at 27 deg C. And all to get home in one leg!!

With an aircraft that weighs 21,000lbs and 2 engines pushing out 3,000lbs of thrust each an engine failure at rotate would not be pretty. Even at MTOW the distance to get to 1500ft would be about 15nm on one engine.

Camelspyyder, If you as PIC allowed your PA to overfill your aircraft by 600lbs that was your responsibility!

camelspyyder
11th Aug 2017, 10:06
No no, I was the retard PA.

However, my P1 was a WIWOL type and coped admirably.

Just This Once...
11th Aug 2017, 12:36
The acute concern with the Phenom is its performance in role. The asthmatic and increasingly heavy Dominie only resorted to single engine for conversion & BTRs for experience pilots.

The Phenom will be our multi-engine training aircraft so will spend a good deal of its time on one engine with an ab-initio at the controls. Continuing the typical SID when simulating the loss of an engine will either be a challenge or an outright impossibility. Drawing out a typical single-engine climb from Cranwell is both depressing and airspace intensive.

I am sure the little Phenom is a delightful aircraft for the market it was designed for but it is hardly something you would choose if cranking out asymmetric handling day-in day-out is your game.

BEagle
11th Aug 2017, 13:11
How does the Phenom compare with the USAF's T-1A multi-engine trainer?

I note that the latter 'differs from its commercial counterpart with structural enhancements that provide for a large number of landings per flight hour, increased bird strike resistance and an additional fuselage fuel tank.'

Were similar enhancements a part of the procurement requirement for the RAF's new multi-engine trainer?

Perhaps the most bizarre idea for ME training to replace the Pig was a BWoS proposal, using a deflector vane and 2 pretend throttles in a Jet Provost. Asymmetric flying was to have been achieved by closing one 'throttle', which would halve the available thrust and deflect the vane to create yaw.... But then the political Jetstream became available, so the idea never progressed further. EFATOs would have been...interesting!

Dominator2
12th Aug 2017, 14:26
I would point out that on the Dominie we never practiced EFATOs at MTOW. For BTRs we were normally only 2 crew and 6000lbs of fuel i.e. 3000lbs below MTOW. Once a year on the IRT we were 2 crew and full fuel, but that was still 1000lbs below MTOW.

By operating to these procedures there was a small tolerance for slight mishandling. In the later years all pilots were experienced, at least 3000+ hours. We did, however, still have those who reverted to type and produced the EFATO procedure from a previous ac. Enough to cause uncertainty at a critical phase of flight!

I agree with BEagle, apart from the poor ac performance the Phenom does not look to be rugged enough to withstand the rigours for an RAF Multi Engine Trainer. In may satisfy the accountants but will it satisfy the requirement? One does assume that a requirement was set and agreed by the RAF, hopefully with input from 45(R) Sqn

chevvron
12th Aug 2017, 17:09
Civil Phenoms operate public transport flights quite happily in/out of Blackbushe (with one exception) runway length 1335m.

tescoapp
13th Aug 2017, 06:12
Continuing the typical SID when simulating the loss of an engine will either be a challenge or an outright impossibility

In the civil world that went out the window some 15 years ago.

Its usually 1600ft agl straight ahead (depends on the type and your accl alt) then a turn to a locator. If there is hard stuff inside your climb area then you get a none standard which may involve completing the first turn with TO flap and then accelerate.

The phenom 100 at MTOW needs less than 1000m ISA SL

And land at MLW less than 800m

The engines are flat rated at ISA +15 degs.

The fun one is going to be flapless icing increment on or hydraulic issues. I suspect you would be looking at a 3000meter+ runway for landing.

It all depends if you have the ice increment on for departure or not. Most don't and only turn it on after clean up.
Stick shaker gets triggered at 21 deg AoA with it off and 9.5 deg with it on.
Wing stab on has a huge effect as well apparently.

The only example I can find has a Vref landing for MLW using off as 92 knots with all the icing gear turned on it increases to 126knts.

I don't fly them I might add.

I suspect if someone posted in the Biz jet forum someone would be able to give you some proper numbers after doing a couple of runs through the ipad app.

Worth asking for a icing on flapless :D might give a WTF sod that chuckle.

pr00ne
13th Aug 2017, 21:34
CAW operated Dominie T1 from RAF Manby for some years after Strubby was closed. Much shorter runway than that at Cranwell.

Dominator2
14th Aug 2017, 07:29
Strubby is at Sea Level and no obstructions. Makes quite a difference to Dominie perf. If operated correctly I would guess that there were times when the aircraft did not takeoff at 21,000 lbs?

Returning to the Phenom, I just hope that they will be able to carry out the flight profiles required at CWL and not be limited by the aircraft's performance.

On 55 Sqn we lost a number of sorties due to not being able to lift enough fuel to achieve the training aims.

Davef68
14th Aug 2017, 12:40
Isn't a lot of the MFTS course going to be taught on simulators?

Dominator2
14th Aug 2017, 13:13
Davef68 Isn't a lot of the MFTS course going to be taught on simulators?

And your point is?

BEagle
14th Aug 2017, 14:41
EASA has dumbed down most twin jet training to the extent that asymmetric work is normally restricted to a FFS.

But the RAF does not have an intermediate ME trainer such as the Seneca or DA42 on which students learn asymmetric work, neither are RAF pilots taught to the minimum levels required for mere people-tube co-pilots or MPL applicants - so I sincerely hope that their training is to the higher standards required to operate Atlas / C-103J / C-17 / Poseidon / Sentinel / Sentry or Voyager in a tactical environment.

For the next generation of RAF ME pilots, it is crucial that 'live' asymmetric training is not restricted to a simulator for ab initio training.

Davef68
14th Aug 2017, 15:05
Davef68

And your point is?

Just an observation that the performance of the aircraft in certain conditions may not be thought to be relevant if the intention is to teach those elements in simulated conditions.

Although I think Beagle has some very valid points, and it doesn't take into account what might happen if the situation occured for 'real' on another flight.

Dominator2
14th Aug 2017, 17:36
The bizarre thing about Dominie training was that although the RAF does not train for double failures, we did. The Dominie had a very simple device that when a thrust loss was detected from one engine it applied an appropriate amount of rudder to counter the yaw. Consequently, if the pilot forgot to apply any rudder during and engine failure the aircraft would remain in trim

The RAF in its wisdom, when conducting EFATO practice switched OFF the protection device. Consequently, we trained for a double failure, something that never happened in the aircrafts 45 years’ service. If we were teaching ab initio multi engine pilots I could understand but we were NOT.

Does the Phenom have a similar device to prevent yaw in even of an engine failure or does it rely on the pilot’s large boot?

Brain Potter
14th Aug 2017, 22:39
EASA has dumbed down most twin jet training to the extent that asymmetric work is normally restricted to a FFS.

But the RAF does not have an intermediate ME trainer such as the Seneca or DA42 on which students learn asymmetric work, neither are RAF pilots taught to the minimum levels required for mere people-tube co-pilots or MPL applicants - so I sincerely hope that their training is to the higher standards required to operate Atlas / C-103J / C-17 / Poseidon / Sentinel / Sentry or Voyager in a tactical environment.

For the next generation of RAF ME pilots, it is crucial that 'live' asymmetric training is not restricted to a simulator for ab initio training.

EASA have not "dumbed-down" asymmetric training. Regulations have evolved to place the training/checking activity into the most appropriate environment, with due regard for safety and realism. For jet aircraft, actual asymmetric flight in a qualified Level D FFS gives much better quality training than simulating asymmetric flight in an aeroplane. The instructor can fail the engine suddenly, at the most challenging moment and accompanied by the correct thrust decay, warnings, sounds and vibration. Setiing the obvious safety argument aside, this gives much better training than in airborne environment where instructor (slowly) closes a thrust lever and then uses a significant proportion of their capacity safeguarding against the expected critical mistakes, rather than monitoring student performance. I have no relevant knowledge of turboprops but, from what I remember, some sort of residual thrust would usually have to be applied to "simulate" the feathered propeller. The efficacy of such an approxination is less likely to be accurate than manufacturer-approved, certified data that drives the simulator response.

Of course, the RAF do some different things with their aircraft, but the principles of V1 cut, OEI approaches and landings are the same as in commercial aviation. If you can deal with an OEI go-around in a 737-800, you can deal with an engine failure at low level in a P8. If a Level D sim is available, I cannot see a valid argument that justifies the additional risk of conducting live "tactical" training scenarios involving asymmetric flight.

tescoapp
15th Aug 2017, 09:43
I have no relevant knowledge of turboprops but, from what I remember, some sort of residual thrust would usually have to be applied to "simulate" the feathered propeller. The efficacy of such an approxination is less likely to be accurate than manufacturer-approved, certified data that drives the simulator response.

They would close the power lever and then when the memory items were complete you would then be given between 10-15% torque to simulate the feathered engine.

They used to try and give you V1 cuts just after the wheels left the deck but after several Vmca rollovers in the UK at least the stopped that practise and it was only after the gear was up that they "failed" the engine.

Some of the latest EASA pushed training scenarios would be down right lethal in real life. Noise abatement profile V2 +10 climb followed by an inside engine failure in the first turn if they let that wing go more than 15 deg bank you better be quick bringing the power back on the dead engine or reducing the live one. Sim no worry's reset and lets try that again. real aircraft its a new pair of pants at the very least.

Dominator2
16th Aug 2017, 17:45
Just seen the East Jet "Inside the Cockpit" documentary.
https://youtu.be/2qVE4NtW86I
Interesting that no matter how good the Simulator is, it is different for real. Please to see that easy gives ab initios at least one flight prior to being let loose on passengers.

Simulated Single Engine training can be conducted safely with the right instructor in charge. Like many things, the basics should be taught and tested in the sim and then validated in live flight conditions.

One thing that I thought that was good when in the USA was that the same IP did the sims and then the flight with his/her student. At least it meant that in flight you nearly always knew what to expect!!!

H Peacock
16th Aug 2017, 18:28
I agree that the place for practicing your V1 cut is in the sim, but flying sim assy (one throttle at idle) for real should most certainly be encouraged in the instrument pattern on a regular albeit controlled basis.
Yes, its safer to practice it it all in the sim, but flying it for real is most certainly different than in the box, however good the sim!

Brain Potter
16th Aug 2017, 19:02
Easyjet don't 'give' anything. EASA mandate that pilots with no previous relevant experience must perform 6 take-off and landings in the aircraft before the rating can be issued. For pilots with relevant experience, this is reduced to 4 or (if the ATO and Operator have the right approvals) it may be replaced with Zero Flight Time Training. Good as modern sims are, no-one is (yet) ready to accept the risk of letting cadets do ZFTT.

However, the signicant risk of conductng 'live' asymmetric training on a twin-jet does not justify the marginal gain in skills/experince over. doing it synthetically. Even the 'right' instructor can't prevent the live engine failing at the most inopportune moment, so any actual asymmetric training has to bounded with significant safety margins. If the sim allows realistic practice of a V1 cut, is there any additional value in doing it in the aircraft with a safety margin that means the 'failure' is not initated below say 500' aal? If there is no suitable sim (Jetstream T1), then clearly there is no alternative, but if the Phenom has a Level D sim why take unnecessary risk?

Is Phenom coming with a Level D sim? If it is, I really hope that its full capabilities are understood and exploited, with the training sessions being regarded as equal in value and importance as the flying sorties.

BEagle
16th Aug 2017, 20:38
BP, do please remember that easyJet copilots will have had at least some previous asymmetric time on aircraft such as the Seneca or DA42 - whereas RAF ME students will not. So they must surely be given at least some asymmetric training on the Phenom; not a V1 cut at MTOM, but certainly some asymm handing, asymm approaches and go-arounds at training weights.

Way back when I first flew the VC10, we had a very basic sim. So pretty well all asymm training was done on the aeroplane. Such as a simulated 3-e t/o with a further failure once the landing gear had been raised, followed by the FI throttling back the 2 live engines 'to simulate Nairobi on a hot day'. Barking mad and very risky in today's culture. But when the improved simulators arrived, student captains only did one brief double asymm exercise in the aircraft. 3-e work was also reduced to the minimum deemed safe and we even did IRTs in the box later on. Which was a $od as the box lacked the upgraded aircraft instrumentation - no FMS RDU, for example.

High risk asymm should really only be taught / practised in a FFS, but at least some ab initio asymm work must still be flown in the aircraft.

Brain Potter
16th Aug 2017, 22:40
BEagle,

I do see your point about initial exposure to asymmetric flight. But simulated OEI in a twin-jet (even a small one) when close to the ground is not something that I regard as prudent, or necessary if a simulator is available. It could go horribly wrong if an engine quits on an OEI go-around. Perhaps they have picked the wrong aircraft.

The MPL scheme does not involve any live asymmetric training; it is all done in simulators. And it seems to produce first officers that are perfectly acceptable to Easyjet who, I happen to know, have high standards.

Of course, RAF training has many necessary differences from civil, but I don't agree at all that military pilots have, or need, any greater skill in handling asymmetric conditions than airline pilots. That said, I have no knowledge of airborne delivery, so ithere may be some nuance of turboprop flying when low/slow and dropping stuff that I haven't appreciated. I do know that a 737 can be a handful when OEI and that MPL cadets are coping, despite the lack of MEP class experience.