Tag Archives: Controlled Flight Into Terrain

Close call: Boeing 737 almost crashes into the water while landing into St. Maarten

A WestJet B737 Demonstrates How the Famous Princess Juliana Approach Can Be Tricky.

Every aviation enthusiast knows about the approach to St. Maarten’s famous Princess Juliana Airport and the remarkable views of aircraft landing there from Maho Beach directly in front of the runway threshold.

While this has always been a great place to celebrate aviation, it can also turn dangerous.

On March 7, Tuesday, WestJet flight 2652 from Toronto was making a descent through a low ceiling to Princess Juliana. The first attempt through rain and low cloud cover was videotaped and photographed by plane spotters who are almost always at Maho Beach to watch incoming aircraft. On that Tuesday they caught a near miss: a near Controlled Flight Into Terrain (CFIT).

The first approach puts the Toronto flight short and low, low enough that jet wash from the Boeing can be seen creating turbulence on the surface of the water. The flight crew does an excellent job of immediately applying power and going around for a second approach. Commercial flight crews, and especially those trained and, in some cases, specially certified to fly into airports with unusual approaches, are well-drilled both in the simulator and as 2nd officers for flights into these airports before captaining a flight there.

Even with the low cloud cover the second approach in the video has a higher trajectory, is more on glide slope presumably and has no problem coming in safely over the water and clearing the famous fence at Princess Juliana.

The video is noteworthy since incidents like this at Princess Juliana, St. Maarten are actually very rare. According to at least one source, there has never been an accident recorded on the final approach to the famous runway 09/27 at Princess Juliana (even though it’s pretty obvious there have been several near-CFIT incidents and actual mishaps by civil and military aircraft crashing short of the runway at the end of a final approach in both good and bad weather in aviation history). This further speaks to the special training commercial pilots undergo to fly the route.

While there have been conversations about closing Maho Beach to the public for safety reasons it has remained open since there have really been no significant accidents for observers on the ground and it remains a sensational attraction for tourists and aviation enthusiasts alike.

Video credit: ATCpilot.com


Watch an F-16’s Automatic Ground Collision Avoidance System save an unconscious pilot from certain death

The Automatic Ground Collision Avoidance System (Auto-GCAS) recognized the F-16’s dangerous attitude and automatically performed the recovery that saved the life of an unconscious student pilot.

Obtained by Aviation Week, the declassified footage below shows the importance of Ground Collision Avoidance Technology (GCAT).

It was filmed from the HUD (Head-Up Display) of a U.S. Air Force Arizona ANG F-16 whose student pilot was rendered unconscious by high-G BFM (Basic Fighter Maneuver) up to 8.4g during a training flight.

With the pilot suffering G-induced loss of consciousness (G-LOC) the aircraft started an uncontrolled steep descent from 17,000 feet in full afterburner.

You can clearly hear the worried IP (Instructor Pilot) radio “Two, recover!”, three times as the aircraft, 55-degree nose down, thundered towards the ground at more than 600 knots.

When the aircraft seems to be destined to hit the ground, the Auto-GCAS detects the unusual attitude and executes a recovery maneuver at around 8,700 ft. and 650 kt, saving “Sully 2” from CFIT (Controlled Flight Into Terrain).

We have analysed GCAT in depth with an article by USAF Flight Surgeon, Capt Rocky ‘Apollo’ Jedick, last year.

As explained in that story, two of the most common human factors conditions that lead to death or loss of aircraft in combat aviation are spatial disorientation and G-induced loss of consciousness (G-LOC).

Spatial Disorientation is the inability to determine one’s position, location, and motion relative to their environment. The Pilot-Activated Recovery System (PARS) will save pilots suffering from recognized Spatial-D as long as the pilot remains able to activate the technology. If a pilot is spatially disoriented but remains unable to initiate PARS, Auto-GCAS should theoretically still save him/her from CFIT.

Auto-GCAS provokes inputs to the flight controls automatically without pilot initiation. The technology relies on sophisticated computer software, terrain maps, GPS and predictive algorithms that will ‘take the jet’ from the pilot when CFIT is predicted to be imminent.

Although Ground Collision Avoidance Technology has proved to save several lives (this is the fourth confirmed “save” by the Auto-GCAS system since the system was introduced in 2014 according to AW’s Guy Norris) it has some significant software and hardware limitations.

For example, as we highlighted last year, the system is not able to make inputs on the throttle. If the power reduction is required for the optimal recovery GCAT systems (as Auto-GCAS and PARS) might be  unable to initiate recovery overriding the current throttle setting.


New video shows Blue Angel #6 crashing in Smyrna, Tennessee

A new video that appears to show the Blue Angels crash in Tennessee has been posted online.

A new video uploaded to Youtube yesterday seems to show the deadly crash that killed Capt. Jeff Kuss, Blue Angel #6 during a practice flight at the Smyrna Airport, Tennessee, on Jun. 2.

The clip shows the Lead and Opposing solo depart: whilst the #5 performs the dirty roll, the #6 performs a low transition and at 285 KCAS he pulls to 70 degrees nose up. According to the Blue Angels Maneuvers Manual at a minimum of 3,500 feet, he would roll the aircraft 180 degrees and complete a Split S reversal.

The footage shows the doomed Hornet almost leveling off at the end of the maneuver beyond the trees before a smoke and fireball is caused by the impact with the ground.

Did the pilot reach the required 3,500 feet? Did something else fail? Did the pilot suffer a G-LOC (G-force induced Loss of consciousness)?

The video does not help answering those questions, still it provides some new details about the deadly crash.

H/T to our pal Tyler Rogoway at The War Zone for posting the video.



No, Auto-GCAS could not have prevented the Germanwings crash

Several articles have mentioned the A-GCAS (Automatic Ground Collision Avoidance System) as the military tech capable to avert the Germanwings crash.

We recently run a very detailed article about GCAT (Ground Collision Avoidance Technology), the umbrella term for a whole variety of technologies and applications in military, commercial, general and unmanned aviation aimed to prevent CFIT (Controlled Flight Into Terrain) incidents.

The Auto-GCAS (Automatic Ground-Collision Avoidance System) is an automatic system that, once installed and activated on a plane, monitors the flight parameters: to make it simple, when predictive algorithms and computer software determine that altitude, speed, attitude, GPS position, terrain are such that the CFIT is imminent, the A-GCAS automatically (without pilot initiation) sends inputs to the flight controls to recover the plane.

Developed by NASA and deployed to the U.S. F-16 fleet, A-GCAS is already credited for saving the life of a Fighting Falcon pilot involved in Operation Inherent Resolve (along with several other ones).

Will Auto-GCAS technology transition from military to civil aviation in the near future?

Whilst it’s safe to say believe technology behind Auto GCAS may one day make its way to the civilian aviation we should not forget that  airliners are less prone to those kind of issues (like spatial disorientation or GLOC) that make the A-GCAS so important for jet fighters. Moreover, civil planes already feature several kinds of GCAT (Ground Collision Avoidance Technologies) that address the most common threats to the airliners.

Could such technology have prevented Germanwings crash?

Dealing with the impact the A-GCAS would have had on Germanwings CFIT, it’s safe to say that it would not have prevented the aircraft from being deliberately crashed into a mountain: A-GCAS or PARS (Pilot Activated Recovery System) are safety systems based on the assumption that pilots wants to save their planes.

The A-GCAS as it is now, must be activated by the pilot: once activated it can’t be overridden (the computer will recover the plane taking over command of the plane), but a pilot who wants to commit suicide has the option to disarm it.

Until a new version that can’t be disabled is introduced, the pilot will have the possibility to crash his/her plane on the mountain.

Furthermore these systems have some important limitations: for instance A-GCAS can’t make inputs to the throttle meaning that a pilot who wants to crash a plane may theoretically reduce throttle to idle to disable A-GCAS.

Then there is also another aspect to take into consideration: all the technology aboard a plane can become unreliable and any automatic sense-and-avoid system which acts on the flight control based on information gathered by failed sensors can become useless or even dangerous for the safety of the plane.

There are many examples (Air France 447 is among them) in which bad instrument readings, clogged pitot tubes, sensors suffering failures, etc. have been contributing factors to aviation disasters: that is the reason why pilots are usually given the possibility to disarm every onboard system, including (on military planes only, at least for the moment) the A-GCAS.

Image credit: Sebastien Mortier


Russian Sukhoi SuperJet-100 goes off radars in Jakarta during demo tour: Controlled Flight Into Terrain and Hijacking not ruled out

On May 9, at 15.30LT, a Russian Sukhoi Superjet 100 (95004), involved in a demo tour in southeast Asia, with 46 people on board has disappeared from radars, approximately 36 nautical miles to the south of Jakarta, during a planned 2,5 hr demonstrative flight from Jakarta Halim Perdanakusuma Airport to Jakarta Halim Perdanakusuma Airport (Indonesia).

[This one uploaded to Foursquare, taken on the ground is one of the last images of the doomed aircraft.]

Obviously, very few details are known at the moment: it looks like the aircraft was cleared to descend from an altitude of 10,000 feet down to 6,000 in area in the vicinity of Mount Slak (7,500 feet) and Mount Gede (9,000 ft), and radar contact was lost as the plane crossed 6,200 feet, moving downwards in a rightward direction.

Obviously, it’s too early to speculate, based on the fact that the crew did not broadcast a mayday call, the main causes of the crash (provided that the incident was a crash and the aircraft did not ditch somewhere) seems to be a CFIT (Controlled Flight Into Terrain), possibly caused by the fog and bad weather conditions in the area.

Indeed, according to the first news agencies the search and rescue operation was hampered by rain, fog and the approaching dusk.

Controlled Flight Into Terrain, that we have discussed on this blog reporting about last year’s Blue Angels near crash during an airshow, is a frequent kind of accident in which an efficient and airworthy plane, underpilot control, is unintentionally flown into the ground, a mountain, water, or an obstacle.

What is weird is that the aircraft disappeared at 6,200 ft while flying under IFR rules and radar control had cleared it to 6,000. Did the crew descend below the radar minima? Or did the ATC clear plane below radar minima?

At the same time, hijacking has not been ruled out, as reported by Russia Today. Along with the Russian crew there were 36 representatives and potential buyers from many different countries.

In fact, the Russian plane arrived in Indonesia on the fourth stopover of its Asia demo tour: after visiting Myanmar, Pakistan and Kazakhstan it was supposed to perform demo flight in Laos and Vietnam, after Indonesia.

The aircraft went missing on May 9 was featured on the Sukhoi Superjet 2012 calendar that you can see below.