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Accident description
Last updated: 9 December 2016
Status:Final
Date:Wednesday 13 July 2011
Time:06:54
Type:Silhouette image of generic L410 model; specific model in this crash may look slightly different
Let L-410UVP-E20
Operator:NOAR Linhas Aéreas
Registration: PR-NOB
C/n / msn: 2722
First flight: 2010
Total airframe hrs:2126
Cycles:3033
Engines: 2 Walter M-601E
Crew:Fatalities: 2 / Occupants: 2
Passengers:Fatalities: 14 / Occupants: 14
Total:Fatalities: 16 / Occupants: 16
Airplane damage: Destroyed
Airplane fate: Written off (damaged beyond repair)
Location:1,7 km (1.1 mls) SSE of Recife-Guararapes International Airport, PE (REC) (   Brazil)
Phase: Initial climb (ICL)
Nature:Domestic Scheduled Passenger
Departure airport:Recife-Guararapes International Airport, PE (REC/SBRF), Brazil
Destination airport:Natal-Augusto Severo International Airport, RN (NAT/SBNT), Brazil
Narrative:
A Let L-410 passenger plane, registered PR-NOB, was destroyed in an accident near Recife-Guararapes International Airport, PE (REC), Brazil. All 14 passengers and two crew members were killed. The airplane operated on NOAR Linhas Aéreas Flight 4896 from Recife (REC) to Mossoró (MVF) with an en route stop at Natal (NAT).
The airplane had taken off from runway 18 at Recife at 06:51.
During the takeoff briefing, the captain said that he would consider the possibility of landing on the runway, if a failure occurred after V1 (decision speed), with sufficient runway and the landing gear still not retracted.
He also said that, if a failure occurred after V1 and with the landing gear retracted, he would proceed with the flight, while the copilot would be in charge of monitoring the instruments and complementing the emergency procedures after 400ft AGL. He informed that, in such case, the turns would be made towards the “good engine” side.
During the takeoff, three seconds after the captain requested retraction of the landing gear, a sound was heard from the engines.
Despite the captain's request to retract the landing gear, his request was only complied with 50 seconds later, after the fourth time he repeated it.
After verifying the engine failure occurrence, the copilot asked the captain to "abort takeoff" three times, adding that the aircraft had lost power. The captain proceeded with the departure, saying that there was not enough space to abort takeoff.
The captain, then, told the copilot to request landing on runway "thirty", repeating this request twice, without taking into account that Recife Airport runway has the thresholds 18 and 36. The copilot, however, informed the Tower controller that the aircraft would proceed for a landing on runway 36.
Shortly after this message, the copilot asked the captain to "lower the aircraft nose". In his reply, the captain asked the copilot to take it easy, and the copilot agreed: "I know, we are at 400ft, let’s fly!".
Then, there was a significant change in the cockpit background noise, with the captain telling the copilot to feather the propellers of engine number 1.
The captain told the copilot to call the Tower, and the copilot asked what his message to ATC should be. The captain instructed him to tell ATC that they were in emergency.
The copilot’s answer to the captain was: "We are in emergency. We are cleared to land on runway 36, let’s go".
Then, the alerts "Don’t sink! Don’t sink!”" and "Too low, terrain" were heard several times.
At 06:52:45, the captain asked the copilot to feather the left engine propeller blades, and the copilot answered by saying that the propeller blades had already been feathered.
At 06:52:52, the copilot asked the captain to turn towards the aerodrome. The captain answered that he was already doing so. Shortly after, at 06:53:02, the stall alert went off.
The copilot then said "eighty-one, lower the nose", and then the alerts "Don’t sink! Don’t sink!" and "Too low, terrain!" were heard.
At 06:53:22, the copilot uttered "one hundred twenty feet" and then a stall alert was heard.
The copilot asked the captain to 'hold the power', and the captain said that 'it was in full power'.
Then, the copilot asked the captain not to hold the nose too much to keep the aircraft from stalling.
He then asked the captain whether they would land on the beach, and received a firm "no" as an answer.
At 06:53:43, the copilot commented to the captain that they were at a hundred twenty feet, and that there was not sufficient height to proceed to the runway, suggesting that they should land on a sand strip on the beach.
The captain replied that he would not land on the beach, and informed that they would land in the "field", instead.
At 06:53:56, the copilot radioed: "“NOAR 4-8-9-6 is... it is going to make an emergency landing on the beach...it is not possible to reach the runway... land here in the sand... land in the sand that does not...”.
Then, the stall alert went off.
The captain, anew, told the copilot that they would not land in the sand, and the copilot replied that they would fall on top of the buildings.
From this moment on, the stall alert continued being heard for 19 seconds up to the time the stall occurred, occasionally intercalated with the alerts "Don’t sink! Don’t sink!" and "Too low, terrain!"
At 06:54:12, the copilot asked the PIC to "please" land on the beach, to which the captain rudely answered that he would not do that.
The copilot insisted, saying that they were not able to reach the runway, and the PIC said: "It’s OK! Leave it to me!"
At 06:54:25, the copilot made a comment to the captain that they were stalling and repeated the comment.
The nose was pitching up until the aircraft stalled, impacting a field close to a road. A fire erupted. The airplane came down in a vacant lot near the beach, located 1700 m from the runway threshold.


Contributing factors
1. Human Factor
1.1 Medical aspect
a) Anxiety - undetermined
The perception of the danger, especially on the part of the copilot, affected the communication, and may have inhibited a more assertive posture, which might have led to an emergency landing on the beach and minimize the consequences of the accident.
1.2 Psychological aspect
1.2.1 Individual information
a) Attitude - undetermined
The operational actions taken in face of the emergency may have resulted from the high level of the PIC’s self-confidence obtained in his years of experience in aviation, as well as from his resistance to accept opinions that were different from his own.
b) Emotional state - undetermined
From the CVR data, it is possible to observe an accentuated level of anxiety and tension in face of the abnormal situation. These components may have influenced the judgment of the conditions affecting the operation of the aircraft.
c) Decision making process – a contributor
The PIC’s insistence on proceeding to runway 36 after the onset of the emergency, even after the copilot’s realization that they were no longer able to reach the aerodrome, reflects an inappropriate judgment of the operational information presented.
d) Stress evidence - undetermined
The unexpected emergency situation during the takeoff and the lack of preparedness to deal with it may have generated a level of stress in the crew, affecting their operational response.
1.2.2 Psychosocial information
a) Interpersonal relationship – undetermined
The history of divergences involving the two pilots possibly hindered the exchange of information between them, creating a barrier for dealing with the adverse situation.
b) Team dynamics – a contributor
The presence of diverging ideas in relation to the actions to be taken and the way they were treated, revealed cockpit integration and coordination problems that made it difficult to choose the best option for a safe landing when the aircraft could no longer reach
the aerodrome.
c) Work-group culture – undetermined
The company was informally divided into two groups, whose interaction was difficult. It is possible that this interaction difficulty was reflected in cabin management during the emergency, since this flight had a crewmember from each group.
1.2.3 Organizational information
a) Training – a contributor
The failures that occurred in the company’s training process affected the performance of the crew, since they did not have a conditioned behavior regarding the adoption of safe actions in response to the emergency.
b) Organizational culture – a contributor
The actions taken by the company indicate informalities that resulted in incomplete operational training and in acts that compromised safety.
1.3 Operational aspect
1.3.1 Concerning the operation of the aircraft
a) Application of flight controls – a contributor
According to the FDR data, the pedal was not applied in a way that would allow a deflection of the rudder sufficient to maintain the coordination of the aircraft from a certain moment of the flight with asymmetric power.
The drift values obtained on account of the inadequate application of the pedal penalized the aircraft performance, rendering it impossible to maintain a climb gradient or even a leveled flight.
In the final phase of the flight, even with the decrease of the speed to values below the VMCA, in the midst of the continuous sound of the stall alert and repeated requests by the copilot to not “hold the nose so as not to stall”, the PIC continued actuating in the pitch control until the aircraft reached a longitudinal attitude of 18º and stalled.
b) Cockpit coordination – a contributor
The delay in retracting the landing gear after the first request made by the PIC, the command of the PIC to feather the propeller blades when they had already been feathered, and the request made by the copilot asking the PIC to turn towards the airport when the aircraft was already turning, were indications that the flow of tasks in the cockpit was not well coordinated.
The emergency procedures prescribed in the checklist were not complied with. In the final moments of the flight, there was not agreement between the pilots as to defining the least critical option, i.e., either return to the aerodrome or land on the beach.
c) Forgetfulness – undetermined
It is possible that, in face of the emergency and under a feeling of anxiety, the pilots forgot to perform the third segment of the procedure prescribed for the takeoff engine failure above V1 emergency, attempting to return to the aerodrome just after the conclusion of the second segment, still at an altitude of 400ft.
d) Training – a contributor
The lack of training of the takeoff engine failure above V1 emergency, in the exact way it is prescribed in the Training Program, favored an inadequate performance in face of the problem they were confronted with.
The pilots did neither follow the flight profile recommended for the emergency, nor executed the checklist items prescribed after the 400ft.
e) Pilot judgment – a contributor
The pilots judged that their priority would be to return for a landing on the runway, but in the opposite direction from the one they had used for taking off, with the turn starting at 400ft, a fact that made it more difficult to fly the aircraft.
Up to 400ft, the aircraft maintained a straight flight profile and developed a positive climb gradient. This flight condition favored the accomplishment of the emergency checklist items, in accordance with the prescriptions of the Training Program, with little variation in the application of the flight controls.
Upon starting the turn, it would be necessary to find a new measure of pedal deflection compatible with the new condition of banking, and, at the same time, perform the checklist procedures. Therefore, the turn itself represented an increase in the workload. It is worth stressing that the operating engine had appropriate power for the maintenance of the flight.
f) Management supervision – a contributor
The supervision by the management did not detect that the instructions given omitted items of the syllabus contained in the Training Program relative to the takeoff engine failure above V1 emergency, both in the ground curriculum and in the flight
curriculum segments.
No-one identified that the software being used by the company for the dispatch of the aircraft performed the calculation of the maximum takeoff weight, attributing to the maximum takeoff weight for a takeoff from Recife a value that was in fact the maximum structural weight (6,600Kg).
On the day of the accident, there was a weight limitation on account of the temperature. Due to the inbuilt failure of the software, the aircraft took off with an excess in the takeoff weight, resulting in a reduction of the rate of climb.
2. Material Factor
2.1 Concerning the aircraft
a) Manufacturing – undetermined
Considering the hypothesis that the fatigue process in the blade T52A175 had its origin while the blade was still installed in the Russian operator engine, the method utilized by the engine manufacturer for the evaluation and later reutilization of the used blades would not have been able to guarantee the quality of that blade, which ended up being installed in the position number 27 of the accident aircraft left engine GGT disk.
b) Design – undetermined
The aircraft documentation translated to the English language by the manufacturer did not favor the operation of the aircraft, as it contained confusing texts, differences within a same topic when dealt with by distinct documents, along with translation errors, which made it difficult to be understood, and which may have contributed to the non-execution of the proper procedure relative to the takeoff engine failure above V1 emergency.
Especially in regard to the "ABC switching off" action, to be taken at 200 ft, the divergence between the ways it is presented by the checklist and the AFM may have contributed to its non-execution by the pilots, degrading the performance of the aircraft.

Classification:
Loss of control

Sources:
» G1
» Força Aérea Brasileira


Follow-up / safety actions

CENIPA issued 23 Safety Recommendations

Show all AD's and Safety Recommendations

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Map
This map shows the airport of departure and the intended destination of the flight. The line between the airports does not display the exact flight path.
Distance from Recife-Guararapes International Airport, PE to Natal-Augusto Severo International Airport, RN as the crow flies is 248 km (155 miles).

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Let L-410

  • 103rd loss
  • 1138+ built
  • 11th worst accident
safety profile

 Brazil
  • 66th worst accident
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