By Dr. Sunjoo Advani, IDT-SCS

A regulatory mandate goes a long way in convincing us to take action.

The year was 2019. Airlines were undergoing simulator upgrades to either FAA Part 60 Change 2, or EASA CS-FSTD(A) Issue 2, where the new UPRT requirements for training devices were staunchly stipulated. “You can’t do any UPRT without these updates”, was the adage within the community. To a great extent, a correct statement: The aerodynamics, motion buffet and instructor feedback in older devices were unsuitable for conducting full-stall training and certain upset maneuvers, leaving instructors “blind” to what the airplane was doing.

These upgrades were quickly administered, and airlines started training UPRT to their instructors and pilots with these enhancements. The training was either given as a separate short-course, or packaged within a recurrent cycle - or sometimes merely as a new chapter in a manual, with no additional instructor training. Regardless of how it was done, the UPRT box simply had to be “ticked” in time to prevent being frowned upon - and disqualified - by the authority.

Then came 2020 and, as we know, air traffic dug its heels. Conversely, training departments were often running faster than ever, trying to keep up with maintaining qualification, and preparing for the end-of-COVID starting gun to be fired. As a result, airlines continued to find innovative ways to check the UPRT box, gasping a sigh of relief when it was “job done.”

Fast forward to early 2024: That gun has fired, and we are all busier than ever. 

Captain Anil (while this story is accurate, his real name has not been used due to privacy reasons) smiles as he exits the simulator, crossing the access bridge like an admiral leaving his ship. Yet, he leaves puzzled, with a new sense of realization: “Why did I not know this all these years? Why did no-one ever teach me these things?”, he asks me, referring to the “new” UPRT “2.0” that he has just been given.

A senior commander in his major airline, he is a skilled, experienced pilot. Yet, today he is truly humbled. Having just undergone a far more comprehensive iteration of UPRT than the “quick fix” course of a couple of years ago, Captain Anil’s mind is filled with wonder. During the debriefing session, he proclaims that, in his two decades flying the most advanced fly-by-wire airplanes, he had never been taught – or even thought about – some of these basics. What was also striking was his admission of how critical these lessons would have been in a real in-flight upset.

And yet, in 2019, his airline entertained the regulator’s request to upgrade its simulators, deliver the exercises, and hurriedly check compliance.

So, what’s the difference?

While FSTD manufacturers, in close collaboration with the airplane manufacturers, earnestly provided enhanced flight models, thereby giving the instructor better tools to conduct UPRT, this facelift did not on its own change the heart of the training process: The instructor.

Empowering an instructor with impressive tools is one thing. Developing instructor competency to use all available tools and squeeze out the full benefits of the device is something altogether different.

 Instructor KnowledgeCAT Sunjoo UPRT 2.0 IMG_1247 2 copy (1).jpg

IDT-SCS UPRT instructor, Dr. Sunjoo Advani (right) demonstrates UPRT concept to former CEO of Sriwijaya Air, Captain Ardhana Sitompul. Source: IDT-SCS. 

Within airlines, ground and flight instructors often inherently miss the same knowledge that pilots may have forgotten regarding basic flying skills. The genesis of this knowledge is learned during licensing training, but which: a) is not thoroughly re-visited during airline training; and b) which actually differs from the single-engine piston airplane where those basics were first taught.

Some examples of these “lost basics”:

  • The stall characteristics of a swept-wing jet can be very different from single-engine piston training airplanes, posing different challenges (and leading to startle). A pilot may tend to resolve the undesired response, forgetting to first reduce angle of attack;
  • Transport-category airplane structures meet certification standards, dictated by finely balancing safety and economics. Aeronautical engineers are proud when a structure fails just a hairline beyond the design limit load, meaning that the wings will manage loads up to their design limit, but no more. Pull hard (to beyond the ultimate load, which is 1.5 x the limit load) during a high-speed, nose-low recovery, for example, and the wing could even encounter structural damage, or fail. Hence, treat her gently!; and
  •  Automation, envelope protection and a host of safety-enhancements reduce the likelihood of upsets to extremely low rates. However, history has still shown that when upsets do happen, pilots often revert to improper skills, or simply don’t have what it takes to recover in a timely manner.

Sriwijaya 182 AccidentCAT Sunjoo UPRT feature Photo 1 thumbnail_Sriwijaya 182 Upset.jpgSriwijaya Air flight 182 (2021) entered an upset due to an asymmetric engine thrust setting, causing the airplane to roll abruptly when the autopilot was disengaged. The airline is now undergoing its next-generation UPRT training. Source: Author. Image Credit: KNKT National Transportation Safety Committee of Indonesia.

The demise of Sriwijaya Air flight 182 is a good example: The 737-500 departed Jakarta on 9 January 2021, carrying 62. When levelling off at FL110, the autothrottle attempted to reduce thrust to maintain the selected speed. The autothrottle system command was unable to move the right thrust lever due to friction or binding within the mechanism. Maintenance records showed that this A/T problem had been reported 65 times since 2013, and remained unsolved.

Because the right thrust lever was jammed in a high-thrust setting, the left thrust lever was reduced to almost idle thrust by the autothrottle system while trying to maintain the lower target speed, resulting in an asymmetric thrust condition.

When the autopilot was disengaged, the ailerons neutralized, and the large thrust asymmetry caused the aircraft to roll abruptly to the left, entering an upset. The pilot was unable to recover. 

All 62 persons on board were killed. The final report also suggests that inadequate UPRT had been provided to the pilots.

The airline, - working with the Directorate General of Civil Aviation of Indonesia, has embarked on its new UPRT program to thoroughly cover all the basics, systematically teaching recognition and recovery.


UPRT 2.0CAT Sunjoo UPRT feature Sriwijaya Upset Lessons Learned.002 (1).jpgTeaching flight fundamentals, including the differences between training airplanes and modern jets, how trim systems behave, angle-of-attack, etc. are considered critical. Here, the effect of asymmetric thrust on the airplane is illustrated. Source: Author Credit: © 2024 IDT b.v.

What’s new in “UPRT 2.0”? 

Here are some examples of what these training programs may contain:

Understanding trim: Invariably, upset events have occurred with an out-of-trim airplane, and a crew that was unaware of the trim state. Simply placing the simulator in an upset while in a trimmed state, may not expose the pilot to elicit the required response. In the universally-defined upset recovery templates, airplane manufacturers wrote “apply trim as needed.” Training programs therefore need to develop a much deeper understanding and appreciation of longitudinal and lateral trim;

Understanding angle of attack: Stall, which by definition is a “loss of control”, is a function of one single parameter: Angle of attack. Not speed. Not attitude. Even today, there are pilots who may not comprehend this basic principle and, more importantly, how to maintain a safe angle of attack. This information is often available through multiple indicators on most flight decks - and blatantly visible when properly taught;

Understanding swept-wing aerodynamics: A swept wing under sideslip produces asymmetric lift, regardless of the physical dihedral angle. This is called the “dihedral effect”, and can cause instability. Put a swept-wing in a sideslip, and it will roll; and

Understanding the human factor: The simulator will be the foremost tool for UPRT, yet it is earth-fixed - and, like Captain Anil, we always walk over the bridge after the session. Teaching the difference between simulation and reality imposes its own challenges, requiring a balanced approach to prevention and recovery.

Ultimately, we need to not only prevent the aerodynamic stall, but also “brain stall” of the pilot. We can never completely remove the startle from that pilot. However, we must try to manage the startle response with proper techniques that are universal, correct, aligned with the airplane manufacturer, and easy to apply. Familiarity with successful recoveries develops confidence.

CAT SUnjoo UPRT 2.0 IMG_0856.jpg

In-seat instruction is critical to "UPRT 2.0," as it enables an instructor to conduct demonstrations that may include non-standard flying techniques. These illustrate (above) for example, aerodynamic concepts and airplane flight characteristics. Source: IDT-SCS.

Back to the Instructor

UPRT is a complex subject, requiring thorough training of instructors. A one-time UPRT course may be considered adequate for meeting regulations. Yet, this is just bare-minimum. The subject is both broad and deep, requiring much time and energy to address properly. We can, should and must aim to do better.

FSTDs now provide powerful tools to the instructor to see how a student performed their recoveries. Yet, should these fancy tools require the instructor to be absorbed in the tool itself, like a modern-day toddler behind an iPad? Shouldn’t the instructor’s main focus remain on observing the pilots, while monitoring their handling of the delicate airplane at the same time?

The good news is that it is possible to do both: A proper UPRT program will also teach an instructor that virtually ALL the airplane flight envelope information and limitations are also present on the primary flight display. This allows instructors to focus on the training, rather than the tools alone – and its revelation leads to responses that are thrilling to witness!

The fact is, an upgraded simulator and an average instructor will yield average results.

However, an excellent instructor, given almost any qualified simulator, from average to an upgraded device, utilizing a properly-designed training program, is more likely to bring about excellent results.

The bottom line: Invest in your instructors, and continue to upgrade their competencies, especially in areas that have been left behind for so long, like UPRT.

Ultimately, recoveries must simply be taught to be “bullet-proof.”  This takes a comprehensive, long-term program, balancing prevention and recovery. Had the Sriwijaya crew received such training, the outcome may have been different.

UPRT is a complex subject, and we cannot simply check the box. Compliance alone will not guarantee safety.

We need to reflectively look at our pilots’ training needs, and the programs we provide them.

Are we truly at the “next-level” of UPRT, or are we just getting off the ground?

Editor’s note: Dr. Sunjoo Advani, a PhD in aerospace engineering, is an expert in flight simulators and training. He served as Assistant Professor of Aerospace Engineering at the Delft University of Technology where he also developed the SIMONA Research simulator. He initiated and chaired the ICATEE committee of the Royal Aeronautical Society which developed the basic requirements of UPRT for ICAO and industry. His company IDT, which is also part of Starr Consulting Services (SCS), supports national authorities and airlines in safety-critical flight training, including UPRT and a new landing-training program called “Final Approach Standardisation Training.” Starr Consulting Services is part of Starr Insurance.