Menu Sign In Contact FAQ
Banner
Welcome to our forums

How often do SE IMC pilots practice limited panel/engine failure/PFL procedures?

While the EASA CPL SE has PFL exercises in a complex single in VMC, neither the IMC or IR requires a PFL under simulated IMC conditions for the SE rating.

The FAA requires a limited panel non precision approach for some IR rides, in addition to the unusual attitudes recovery with limited panel required by EASA. The FAA ATP SE ride also requires limited panel approaches to stall and slow safe speed, and glide descents, but no ride or recurrent test profile actually requires a descent under simulated IMC with a simulated engine failure on stand by limited panel, navigating to an emergency landing site followed by a PFL in bad weather circuit VMC. Some FAA rides capture elements of these, but not necessarily together.

In addition partial panel (loss of pitot/static) is not part of test profiles.

As a consequence if it’s not in the practical test standards, ATOs don’t typically train for them, but shouldn’t the SE IFR pilot practice these on a regular basis?

The SE turbine ATOs do train these scenarios in the simulator but with much better systems redundancy the scenario may be carried out with the AP.

Perhaps there is an element of spin training, where the risk of a training accident (PFLs in a heavy complex single typically may have a higher risk of an ‘undershat’/hard landing) resulting in fewer PFL being carried out, if at all, even in VMC.

Enstone (EGTN), Oxford (EGTK)

I haven’t seen the distinction between “partial panel” and “limited panel” before. What’s the difference?

ESKC (Uppsala/Sundbro), Sweden

A_A limited implies loss of vacuum/gyro/ADAHRS, partial refers to loss of pitot/static. This may be a UK terminology, in the US partial panel IFR is used for less of gyros.

Enstone (EGTN), Oxford (EGTK)

US terminology. Partial panel = no vacuum instruments. Limited panel = no pitot/static instruments.

[edit: already answered above]

Last Edited by Cobalt at 28 Dec 21:19
Biggin Hill

I think you have to know the answer to your personal SE cloud base acceptable limits to analyse this – if you’re happily flying over a cloud base approaching minima then an engine failure into forced landing is pretty much going to be a CFIT.

Now retired from forums best wishes

If you break cloud in say OVC002 conditions it would not be a CFIT, and quite possibly having some extra speed would assist in reaching a suitable touchdown site.

I recall having had a discussion of this with a very experienced ex-military (F4) pilot who also flies bizjets. He was involved in some tests of this concept i.e. in such conditions it can be better to descend at a high speed. Obviously the risk is that if you never get visual then you will end up very dead.

Most people would go for the lowest sink speed, which is achieved with max flap AFAIK. Flying at Vbg is pointless when you have no idea what is below.

Administrator
Shoreham EGKA, United Kingdom

With full flaps you will have a high sink rate.
I would use Vmd – the speed for minimum descent – which results in the lowest rate of sink in a power-off glide, providing the longest time in the air. The lowest rate of sink is about 90 percent of Vbg for most airplanes. Just a little slower than Vbg will do.
Once I became visual I would use full flaps to slow down further for the landing.

Last Edited by Flyer59 at 29 Dec 11:26

F59 don’t want to sound like the Principles of Flight flying squad, but Vmd is minimum drag, also best glide and derived from the thrust and drag curves. You would use calculus to get the minimum condition of the drag curve to arrive at Vmd. Vmp is speed for minimum rate of descent, max endurance, and is mathematically .76 of Vmd, and derived from the power available and power required curves, being the minimum condition of the power required curve (Drag x TAS).

The theory is that the SE turbines have approximately 30-40 nm gliding range from end of emergency descent cruise, having carried out an emergency descent to 12,500 feet. They bug Vmd on the AP in speed mode and establish a hold over their emergency landing runway, with the holding fix being the threshold. They aim to cross the last hold at 1,500’ AGL positioning themselves for a downwind performance glide approach at around 800-900’ AGL. Being VMC on downwind might be helpful! They obviously require good systems redundancy, typically multiple batteries and an INAV screen for situational awareness, they also have the ability to feather the prop giving them a L/D ratio of 14~16. Finally they have two hundred foot range landing lights. While some type conversion schools train this drill am not sure whether it has ever been executed in a real life engine failure.

The FAA is very keen on performance glide demo for single engine (landing in a glide from downwind within 200 feet from the threshold with no undershoot).

Last Edited by RobertL18C at 29 Dec 13:49
Enstone (EGTN), Oxford (EGTK)

Yes, you are right, I mixed it up. But the best speed for the minimum is just below Vbg, and then you have to take the wind into accoiunt aswell for the best result. In real life I’d use Vbg, or a little bit slower.

Why take the wind into account if you don’t know what is below? It won’t affect the descent time.

It will affect which way you want to point when you break cloud but that’s true only if you have landing options in the right direction.

Administrator
Shoreham EGKA, United Kingdom
74 Posts
Sign in to add your message

Back to Top