[Peetwo]

Further to last on Sukhoi Superjet Moscow prang - 

Via Oz Aviation...

FLIGHT DATA RECORDER REVEALS FATE OF CRASHED SUPERJET

written by Australianaviation.Com.Au May 21, 2019



The flight data recorder on board Aeroflot flight SU 1492 has revealed key information about the final minutes of the ill-fated Sukhoi Superjet 100 that crashed and burned at Moscow’s Sheremetyevo Airport on May 5.

Forty-one people died in the crash, with a further 10 taken to hospital.

The aircraft, with 73 passengers and five crew on board the flight from Sheremetyevo to Murmansk, was forced to return to Moscow after 30 minutes.

The Superjet had reached FL100 when the crew reported a lightning strike and loss of radio communication. They declared an emergency via their transponder and set course for an emergency landing.

Eyewitnesses reported seeing the aircraft hit the runway hard before bouncing into the air, hit the runway again and burst into flames.

The reports were later borne out by ground observer footage.

Moscow’s Inter-regional Transport Prosecution Office opened an investigation into the accident which will include an assessment of the actions of the crew.

Meanwhile the Interstate Aviation Committee (MAK) has completed work on the contents of the black boxes recovered from the wreckage which show multiple issues during the emergency landing procedure.

According to The Aviation Herald the data was revealed by Rosaviatsia (the Russian equivalent of CASA).

It reported that the flightdeck crew on SU-1492 consisted of the captain (43, ATPL, 6,844 hours total, 1,570 hours on type) assisted by a first officer (36, CPL, 773 hours total, 623 hours on type).




“About 30-40km (16-21nm) west of Sheremetyevo Airport there was rain in clouds, the clouds extended to a height of 8,000 to 9,000 meters (FL262-295) and contained a thunderstorm. The aircraft was climbing through 7,900 feet at 15:08Z when an electrical failure occurred, the flight control system (FCS) degraded to “DIRECT MODE”, the autopilot automatically disconnected; the aircraft was in the middle of thunderstorm activity.

“The captain assumed manual control of the aircraft until the end of the flight. Radio communication, that had taken place on VHF #1 radio so far, became unavailable, the crew was able to partially restore communication via VHF #2 on the emergency frequency only. The crew set the squawk for loss of communication.

“The crew decided to return to Sheremetyevo and performed a manual ILS approach to runway 24L. At the time the aircraft intercepted the glideslope the aircraft’s mass was 42,600kg, which was 1,600kg above the maximum landing weight. The crew deployed the flaps to 25 degrees in accordance with the flight crew operating manual for flight with minimum mode (DIRECT MODE) of the FCS as well as landing above MLW.

“At 15:26Z the crew set the emergency transponder code. Vapp was determined to be 155 KIAS, the descent on the glideslope was stabilised and without any deviation from Vapp.

“Winds during the approach came from 190 degrees at 30 knots. Descending between 1,100 and 900 feet the crew received 5 cycles of predictive windshear warnings ‘Wind Shear ahead, go around!’ Descending through 260 feet AGL the aircraft began to deviate below the glide slope, a ‘GLIDESLOPE’ warning occurred.

“Descending between 180 to 40 feet the engine thrust was increased causing the aircraft to accelerate to 164 knots. At 16 feet AGL the speed was 170 KIAS. A Terrain Awareness Warning System aural signal ‘Retard’ occurred, the engine thrust was reduced to idle.

“At that point the captain began to apply oscillating pitch inputs with increasing amplitude which changed the pitch angle up to +6 and -2 degrees. The aircraft made a “three point” touchdown 900 meters past the runway threshold at 158 KIAS and a vertical load of +2.55G and bounced up to 6 feet AGL. The spoilers did not deploy. In DIRECT MODE they are not permitted to operate automatically and need to be extended manually, however the spoilers were not manually extended by the crew.

Two seconds after the first touchdown the aircraft touched down a second time with the nose gear first at 155 KIAS and +5.85G. The aircraft bounced off again to 18 feet AGL.

“A third touchdown occurred at 140 KIAS in excess of +5G resulting in the destruction of the construction, a fuel spill and fire. While the aircraft was skidding along the runway at 100 KIAS a first fire alarm triggered in the aft cargo compartment, 16 seconds later in the tail section of the aircraft. The aircraft came to a stop 20 seconds after the first fire alarm. Forty seconds after the first fire alarm the fire extinguisher in the tail section was activated. The engines continued to run until end (at 15:31:04Z) of the FDR recording 47 seconds after the first fire alarm.”

A passenger recorded a video of the final approach and landing up to the point of the first bounce.

“The MAK is conducting the investigation which focuses also on the predictive wind shear alerts and the reaction to them.”

(Report with The Aviation Herald).

Extracts from Avherald article:

"..Radio communication, that had taken place on VHF #1 radio so far, became unavailable, the crew was able to partially restore communication via VHF #2 on the emergency frequency only. The crew set the squawk for loss of communication.....At 15:26Z the crew set the emergency transponder code....The engines continued to run until end (at 15:31:04Z) of the FDR recording 47 seconds after the first fire alarm..."

P2 obs: So far there is no indication that the crew actually made either a PAN or MAYDAY call. However sometime after the lightning strike (between 15:08 and 15:26) the crew changed their transponder to squawk 7600 and conducted one aborted approach before changing the transponder to 7700 (emergency squawk) five minutes before the end of the accident landing sequence. Reviewing all of the video footage/phots available it would appear that the first responder fire tanker did not start applying fire retardant (foam) till at least a minute after the evacuation had been initiated.        

Even if we could excuse the fact that emergency services were not put on high alert once the aircraft had suffered a lightning strike which had resulted in multiple aircraft system failures, including a partial comms failure. The Sukhoi Superjet then conducts an aborted approach after which the flightcrew squawk 7700 five minutes prior to the end of the tragic accident sequence. 

Hmm...what's the ICAO Annex 14 required response time again? ref - PDF pg 226/ 9-8 https://www.bazl.admin.ch/dam/bazl/de/do...1_cons.pdf  

9.2.27 The operational objective of the rescue and firefighting service shall be to achieve a response time not
exceeding three minutes to any point of each operational runway, in optimum visibility and surface conditions.

Now consider that recently YMEN was given approval to operate aircraft up to a MTOW of 50 tonne - see HERE :

If you ever wanted a better example of why it is the miniscule McDo'Naught will not even entertain the thought that his aviation safety bureaucracy is taking the Mickey Bliss out of both him and the ICAO muppets, while the slices of Swiss cheese are 'thinned to the absolute minimum required by law' and serious identified aviation safety issues continue to be effectively ignored, then go no further than the following article in the Oz...   

Ironically this is around about the MTOW for a Sukhoi Superjet 100 which, along with the Bombardier’s Global 7500 I believe meets the ICAO aerodrome Cat 6 requirements for an RFF service. But that is irrelevant in Australia because Essendon Fields airport does not meet the Australian standard for a Cat 6 RFFS i.e. > 350k pax per year -   
 However just for shits, giggles and to highlight the bizarre disconnection here in Dunceunda land let's overlay in our mind the Sukhoi accident sequence on RW17 at YMEN:

..The aircraft made a "three point" touchdown 900 meters past the runway threshold at 158 KIAS and a vertical load of +2.55G and bounced up to 6 feet AGL. The spoilers did not deploy, in DIRECT MODE they are not permitted to operate automatically and need to be extended manually, however, the spoilers were not manually extended by the crew. 2 seconds after the first touch down the aircraft touched down a second time with the nose gear first at 155 KIAS and +5.85G, the aircraft bounced off again to 18 feet AGL. A third touchdown occurred at 140 KIAS in excess of +5G resulting in the destruction of the construction, a fuel spill and fire. While the aircraft was skidding along the runway at 100 KIAS a first fire alarm triggered in the aft cargo compartment, 16 seconds later in the tail section of the aircraft, the aircraft came to a stop 20 seconds after the first fire alarm...

From my estimation that puts the touchdown point at YMEN just short of the crossing runway 08/26 (ironically this is about the same position that the B200 VH-ZCR DFO crash aircraft got airborne) which takes the crash landing sequence easily into the middle of the Tullamarine freeway. Now lets replace the B200 that crashed into the DFO with either a Sukhoi Superjet 100 or a fully fueled Global 7500 and think on the bigger fire ball that would have ensued - hmm what was the metro fire service response time again? 
   

...Following the sustained left sideslip, the aircraft began to descend and at 0858:48 the pilot transmitted on the Essendon Tower frequency repeating the word ‘MAYDAY’ seven times in rapid succession. Approximately 10 seconds after the aircraft became airborne, and 2 seconds after the transmission was completed, the aircraft collided with the roof of a building in the Essendon Airport Bulla Road Precinct -Retail Outlet Centre (outlet centre), coming to rest in a loading area at the rear of the building...CCTV footage from a camera positioned at the rear of the building showed the final part of the accident sequence with post-impact fire evident; about 2 minutes later, first responders arrived onsite. At about 0905 and 0908 respectively, Victoria Police and the Metropolitan Fire Brigade arrived... 

MTF...P2