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PA46 weather capability

Unless there was a gyro/pitot issue or wake turbulence, it appears it may not have happened if was equipped with Garmin ESP like the Piper M500. But then some jerk would claim one isn’t a ‘real’ pilot if he employed technically enhanced safety.

The above assumes the airframe was not contaminated as I don’t know how envelope protection behaves with ice.

Last Edited by DMEarc at 31 Jan 16:26

There is one aspect of icing which will affect the PA46 (in all its variants except the Meridian) very quickly. You need to manually bypass the air filter (in the pistons) or turn on the ice ingester (in the JetProp). If you don’t do that, you will lose performance almost immediately. This is more drastic in the initial stages of icing that accretion on the prop, wings or elevator. The previous owner of my plane experienced it himself, he was losing airspeed, could not understand why, IMC but no ice on the wings; he selected alternate air and regained speed instantly. The POH calls for alternate air “in icing conditions”. I select it if in cloud below 5 degrees, ice or no ice.
In the Jetprop, turning on the ice ingester reduces power and increases the time spent in ice.
I don’t know what happened here, obviously, but first thing I’d like to know is if the ice ingester was on…

Last Edited by denopa at 31 Jan 16:35
EGTF, LFTF

could not understand why, IMC but no ice on the wings

In my personal experience with the piston PA46 that is the key to airfilter icing. It does happen below 0 in IMC but exactly in those conditions which do not produce airframe ice. So far whenever there was airframe ice the filter did not ice up.
Before the plane looses airspeed it will losse manifold pressure and the TIT will decrease a little If the air filter bypass is opened and the manifold pressure goes down one inch before the wastegate controller corrects there is no ice and vice versa. Flying with the alternate air door open in IMC below 0 is a good idea but it is very easy to forget about it and then on the ground the engine is without any protection against forein object damage. It would suck any dirt directly into the turbos…

www.ing-golze.de
EDAZ

Denopa says…
‘In the Jetprop, turning on the ice ingester reduces power and increases the time spent in ice.
I don’t know what happened here, obviously, but first thing I’d like to know is if the ice ingester was on…’

This is not exactly the case with a Jetprop….If you have climb power set, say 1200lbs torque and before you enter cloud you would close the ice door which reduces the torque by 150lbs….you simply open the throttle to bring the torque back to 1200 lbs…so no power is lost and no time is lost in the climb.
It would be unlikely the pilot had the ice door open….the ice door needs to be closed when on the ground to reduce FOD damage and the pilot would normally only open the ice door in climb once clear of cloud.
Thats assuming the pilot used the check list and had the ice door closed in the first place?

Here’s what Sebastian was referring to:


Mainz (EDFZ) & Egelsbach (EDFE), Germany

You also get dramatically greater (piston) engine wear, if the air filter is bypassed. I have the oil analysis data to prove it. Whether it translates to an engine being out of overhaul limits when TBO is reached, is a good question… probably not.

Administrator
Shoreham EGKA, United Kingdom

As far as I’m concerned, I don’t follow the second part of his suggestion/sop: I think FOD is a much greater risk to my engine than ice behind the filter once I’ve flown in warm air long enough, and closing the alternate air if OAT>5 is part of my downwind checks.
Edited to say I’m a huge fan of his videos, and his approach: fly every flight the same way, use SOPs and stick to them, debrief every flight.

Last Edited by denopa at 31 Jan 22:54
EGTF, LFTF

I always left the alt air open while in flight. Unless landing on a contaminated rwy I usually closed it as an after landing check. It caused no issues.

Last Edited by JasonC at 31 Jan 23:03
EGTK Oxford

My attitude to that changed after having had to replace two cylinders due to sand in the engine… I’m still not sure what caused that.

quatrelle, that’s a very interesting point. In the Mirage my sop if encountering worrying ice in the climb is to go full power, and I assumed this would be true in the JP, leaving no margin for increased torque. That was based on comments made by JP owners on the MMOPA forums, but I know nothing of turbine operations so I must have misunderstood. That’s good news, I thought this was a definite advantage of the Meridian over the JP…

EGTF, LFTF

The risk in the Jetprop is not using the ice door correctly rather than a loss of power due to its use. If you forget to use it you could have a situation which is suspected in the TBM-850 accident least year. If you close it with high power set, you can overtorque the engine. No evidence that this had anything to do with the accident here though.

EGTK Oxford
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