Pages

Friday, August 9, 2024

VoePass Flight 2Z2283

VoePass Flight 2Z2283 crashed south of Campinas, Brazil, on Friday, 9 May 2024, with 62 (previously reported 61) persons onboard.  PZ-VPB was a 14 year old ATR 72-500 (72-212A).

Every search and rescue operation hopes to find survivors but, given the severity of the event, tragically, all lives were lost. Sorrow for the victims and those that loved them. 

The flight was scheduled from Cascavul (CAC) to Sao Paulo (GRU).



The following aircraft information from: https://www.jetphotos.com/photo/11134705

Reg: PS-VPB

Aircraft: ATR 72-212A(500)

Airline: VoePass Linhas Aéreas

Serial #: 908


Photo from Jetphotos, photographer danilosantosspotter
 https://www.instagram.com/danilosantosspotter/?igshid=YmMyMTA2M2Y%3D


Flightradar24.com has flight data. It appears the airplane plummeted suddenly from about 17,000 feet and crashed after falling more than 12,000 feet in about one minute. 

There was a small upset starting at about 16:21:02 UTC.


The aircraft initially began to lose about 250 feet of altitude and then climbed about 450 feet before beginning the sharp descent at about 16:21:22 UTC.


The airplane appears to have crashed at about 16:22:26 UTC. 



The descent profile was near vertical. Whether the airplane broke apart will be apparent by the size of the debris field.  Whether it broke apart at the start of the steep descent of during the descent will also be apparent by the debris field. 

Video posted online seems to show the airplane mostly intact, spiraling in a flat spin that could have developed from a deep stall (https://www.youtube.com/watch?v=bwxgLoxOND4&themeRefresh=1).  T-tail aircraft are prone to deep stall, as was observed tragically as early as in 1963 on a BAC-111 accident. 

ATR 72 have a stick pusher to prevent deep stall.


Stick Pusher detail from unrelated ATR 72 FCOM

There is not nearly enough data to suggest what happened to cause the initial upset or subsequent steep descent.  Whatever the cause, it was sudden and severe.  The flight data and voice recorders have been recovered.

Severe icing was forecast in Brazil at the time of the accident.  

SBCW SIGMET 9 VALID 091530/091930 SBCW - SBCW CURITIBA FIR SEV ICE FCST WI FL120/210 STNR NC=

Reporting agency: SBCW Curitiba FIR
Significant Meteorological
Sequence number = 9
Valid Aug 09  15:30-21:30 UTC (the accident was at 16:22)
Curitiba Flight Information Region
Forecast Severe Icing
Forecast within Flight Level 120 - Flight Level 210 (accident started from FL170)
Stationary 
No change in intensity


Curitiba Flight Information Region

https://www.flightradar24.com/blog/voepass-atr72-crashes-near-sao-paulo/


The ATR 72 has a sophisticated anti-icing system.  Icing leaves no visible trace in an accident and any factor will have to be determined by analysis from the flight data recorder and voice recorder.





Flightradar24.com ground speed records from this airplane show that the airplane was not transmitting reliable ground speed data.

Flightradar24 considers the ground speed data sent by the aircraft’s transponder to be generally unreliable for this flight. As such, it was not included on the above graph. The aircraft’s transponder did send True airspeed data, which we have processed from the granular data. The graph below shows the last 30 minutes of True airspeed data received from the aircraft.

https://www.flightradar24.com/blog/voepass-atr72-crashes-near-sao-paulo/


Below are records from the accident aircraft on the accident flight, ground speed is amber. Note the rapid fluctuations of more than 100 knots (true airspeed).


Here the previous flight, which was operated normally, showing similar ground speed fluctations.


Here is the same airplane flying 2Z2283 on a prior day, again showing significant ground speed fluctuations.


Finally, here is a plot of 2Z2283 flown by a different airplane, showing much more reasonable ground speed data.





Stay tuned!


Peter Lemme

peter @ satcom.guru
Copyright 2024 satcom.guru All Rights Reserved

Peter Lemme has been a leader in avionics engineering for 43 years. He offers independent consulting services largely focused on avionics and L, Ku, and Ka band satellite communications to aircraft. Peter chaired the SAE-ITC AEEC Ku/Ka-band satcom subcommittee for more than ten years, developing ARINC 791 and 792 characteristics, and continues as a member. He also contributes to the Network Infrastructure and Interfaces (NIS) subcommittee.

Peter was Boeing avionics supervisor for 767 and 747-400 data link recording, data link reporting, and satellite communications. He was an FAA designated engineering representative (DER) for ACARS, satellite communications, DFDAU, DFDR, ACMS and printers. Peter was lead engineer for Thrust Management System (757, 767, 747-400), also supervisor for satellite communications for 777, and was manager of terminal-area projects (GLS, MLS, enhanced vision).

An instrument-rated private pilot, single engine land and sea, Peter has enjoyed perspectives from both operating and designing airplanes. Hundreds of hours of flight test analysis and thousands of hours in simulators have given him an appreciation for the many aspects that drive aviation; whether tandem complexity, policy, human, or technical; and the difficulties and challenges to achieving success.




No comments:

Post a Comment