2016-06-23 18:41:19 2016-07-01 00:39:42 Following my Instrument Rating test it was time to hop into the Slingsby Firefly to experience high g-force manoeuvres and learn to recover from fully developed clean and configured stalls the way an airline pilot should do.
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Upset Prevention & Recovery

That's a wrap on Bournemouth!

Today marks the completion of my flight training in Bournemouth. You might be thinking that the instrument rating test marked the end and in many ways you'd be correct. However, you'd only be correct as far as current regulations go as the not so distant future brings with it a new EASA-mandated training requirement dictating that trainees undergo a mandatory period of Upset Prevention and Recovery training (UPRT) prior to the issue of their licence. Said training is to consist of classroom theory and a number of hours in a suitable aircraft. As far as I understand it the true structure to this new requirement is yet to be finalised but to pre-empt its introduction L3 Airline Academy has set about delivering a form of UPRT as part of its course structures for some time now. Thus after some classroom theory in the form of a mass briefing I was scheduled to complete three training events in the Slingsby Firefly - and what a machine it is!

Given the considerable overlap in the deliverables of the three UPRT flights there isn't much point breaking this post down flight by flight so instead I'll focus on exactly what UPRT is and why it's vital to pilot training going forward, as yes while the lessons are flown in aerobatic aircraft and we get to conduct and see some fairly cool manoeuvres - inclusive of the effects of positive and negative G forces - each lesson really does have its purpose. The teachings could one day save a life, or hundreds. 

With all physical flight training now complete it's time to move out of my Bournemouth accommodation for a small stint back with the parents in Somerset before moving back to Southampton to commence my Airline Qualification Course on the 16th April. Lasting three weeks in duration it is likely I'll be finished on or very soon after my amended timeline of the end of April. In some ways the end of AQC can't come soon enough as I'm so ready to start the job-hunt. That said, I'm also very much looking forward to working in the multi-crew environment which AQC provides, so bring it on.

The remainder of this post is split into sections which can be expanded with a click/tap.


Q: What is UPRT?

Standing for ‘Upset Prevention and Recovery Training’, UPRT aims to provide flight crew with the required competencies to both prevent and to recover from situations in which an aeroplane unintentionally exceeds the parameters outlined for typical operation. Essentially an upset is defined as a condition we should never find ourselves in, i.e. a fully developed stall and thus as trainee pilots we are taught how to prevent entering the given upset condition in the first-place by learning to detect its' early warning symptoms. Further, we are also taught how to recover from the situation should it occur. EASA defines UPRT training as Basic, Advanced and Class or Type specific. The former is completed in basic training, as I'd learnt out in New Zealand, the advanced portion is as taught in the Slingsby during the IR stage in Bournemouth and the type specific stuff is left for your eventual type-ratings. 


Q: Why is the Slingsby Firefly used?

There's no EASA requirement for UPRT to be conducted in the Slingsby Firefly specifically and I presume any form of suited aircraft might be utilised in other schools, but in essence an aircraft of such a type has a much more forgiving airframe when it comes to both positive and negative g-forces and with this in mind an instructor can put a trainee pilot in situations otherwise unsafe for traditional light aircraft. For example, rather rapid entry into a 60° climbing or descending turn might feature as well as push-over manoeuvres, wing-overs and more. Ultimately aerobatic aircraft are the perfect tool for the job. During my time completing UPRT we got close to positive 3 g and negative 0.5 g. The effects of both ends of this spectrum can produce quite disorientating results for the pilot and it was highly valuable to experience the delay to reaction times as a result of feeling heavier than your bodyweight. Granted such g-forces are nothing on those felt by military pilots in fast jets but are sufficient enough to be eye-opening. 


Q: Why is G-force awareness even necessary?

This is quite simply really and it comes down to stalling an aircraft. In straight and level flight an aircraft feels it's normal mass, referred to as 1 g, but if you were to put the aircraft into a 60° banking turn and prevent the nose from dropping by pulling back on the controls you'll then be feeling roughly 2 g. Of course, it's unlikely an airliner would ever bank 60° although irrespective, the g-force felt on the airframe will still increase in the turn.

As a flashback to my time in ATPL Groundschool, an aircraft will stall at a speed which increases in proportion to the square root of the g-force applied to the airframe (load factor). So, let's look at an example. If your Slingsby stalls at 70 knots in straight and level 1 g flight, it would then stall at the much higher speed of 98 knots in a 60° banked 2 g turn. This is simply as the square root of 2 (our g-force) is 1.41 and as such 98 knots is a 41% increase on 70 knots. While the increase from 70 to 98 knots might not appear significant, if you were scale these increases up to the speeds a jet aircraft uses it'd soon become a scary situation.

By demonstrating the link of g-force to the stall speed in this manner we as trainees gain a greater appreciation for the dangers of steep turns in low airspeed situations. Carrying out a steep turn to prevent overshooting the centre line when you're flying 180 passengers could suddenly become a disastrous situation when your stall speed hikes. The opposite effect is also true, however, and by learning how to generate 0 g, or even negative g we can begin to appreciate how the stall speed can decrease to the point of no stall happening at all - such forming the basis of learning how to recovery from an upset.


Q: What are the specifics of the UPRT lessons? 

Lesson One

In the first lesson we're essentially getting used to the aircraft and how it handles. For me, it was also the first time I'd flown using conventional instruments as opposed to the glass cockpit the Garmin provides us with. It took a bit of time to get used to but after a while felt incredibly natural - as expected given the Garmin builds upon the concepts of traditional instruments.

Once used to the aircraft the instructors put us in situations where we feel the typical g-force limitations of conventional airlines - roughly in the region of +2.5 g. We're then told to close our eyes, move our heads etc to feel the physiological sensations learnt about way back in ground school. If you've ever ridden rollercoasters all day long and felt a little dizzy afterwards then I'd describe my head feeling exactly like this post-flight. 

In terms of manoeuvres we then recapped clean stalls at idle power as we've done many a time up to this point before exploring the effects of stalling with power still on. We then looked at stalls with flap. Finally we're shown what negative g feels like and why invoking it as part of stall recovery technique is a totally inappropriate way to recover an aircraft. It's such an uncomfortable feeling and you literally rise out of your seat. I can describe this as the weightlessness you when riding Stealth and Thorpe Park. 

Lesson Two

The second lesson builds on that of the first and aims to teach us how to recover from advanced and more developed stalls. By this point the stalls in question are deemed full aircraft upsets and as such must be recovered from. We are taught to do this using the 'recognise - recover - rebuild' process. During the UPRT flights we presume the aircraft ends up in an upset state due to a lapse in pilot focus. i.e. Looking down at the fuel logs etc all the while autopilot continues to pitch up the nose. In looking up we recognise and say "Nose High - Autopilot Disconnect" before starting to recover. The recovery itself sees us unloading the airframe of any excess g-force strain, bank to 60° and allow the nose to naturally fall below the horizon, regain associated forward momentum / speed before then bringing us back to straight and level flight. With the plane recovered, we set about the rebuild. During rebuild we assess the aircraft performance and altitude whereby the loss / gain of either requires further action to restore the previous pre-upset condition. In a commercial flight the rebuild process would also require us inform air traffic controllers if required, the cabin-crew and of course passengers. The latter party here would perhaps be the most uneasy and scared by the sudden manoeuvres and want an explanation. Once we explore the process of recovery etc we go on to cover incipient spin stalls, wings level accelerated stalls and over banking spiral dives. 

Lesson Three

This lesson is often, as in my case, completed in the same physical flight as Lesson Two given the similarities in its' objectives. In essence we complete the recovery procedures learnt during lesson two under the hood and under instruments. 


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