Crossair Flight 3597 — Aircraft Crash Survival Analysis

Crossair Flight

The paper focuses on the Air crash of the Crossair Flight 3597 on 24th November 2001 and various ways and actions that could have led the plane to survive the air crash. This Aircraft Crash Survival Analysis will not only be highlighting the strategies that could have helped many people survive the air crash but also provides a detailed account of the crash, the reasons the crash took place and the contribution of human error in the crash.

On the 24th of November 2001, Crossair airline’s flight CRX3597, aircraft AVRO 146 RJ 100 registered as HB-IXM, left the Berlin-Tegel airport from runway 26-L at 8 p.m. UTC for Zurich. The flight was scheduled to land at the Zurich runway 14 using the ILS (Instrument Landing System) approach. This approach provides the pilots directions for landing through the radio signals from the airport. The flight was to reach its destination in one and a half hour, but was behind schedule due to the weather conditions. On the other side, the weather conditions in Zurich kept on deteriorating and the visibility for landing worsened due to low cloud cover (Aircraft Accident Investigation Bureau & Swiss Confederation, 2004).

Due to the delay in the flight, the flight scheduled to reach at 21:30 CET was expected to land after 22:00 CET, which meant that the rule of runway 14 being shut down after 10p.m. due to some political issues would come into action. The crew was notified that they would thus have to use runway 28 to stop planes from flying over Germany due to the air noise complaint put forward by Germany. Runway 28, however, did not make use of ILS for landing due its inability to adapt this automated system and thus used a less accurate system of VOR/DME. This system sends radio signals to the crew informing them the accurate distance of the aircraft from the runway and whether it is on the left or right of it. However the system does not provide any information on the altitude measurement of the plane and this is the reason pilots avoided landing on this runway before the political law was enforced upon (syedN07, 2011).

The aircraft that landed before Flight 3597 informed the control tower the adversity of weather due to snowfall and thick fog which thwarted the visibility leading to the runway being visible only from the 2.2nm distance to the aircraft crew. As the flight appeared on the aerodrome control frequency in the control tower and reached the minimum descent altitude (MDA) of 2390 feet, the commander continued descending the aircraft steeply informing the first officer that he has a little visual ground contact. Also the commander, being serving this flight for over 22 years, knew the Zurich airport quite well and thought it was best to keep on descending, thinking that they are almost over the Zurich airport. However, he thought wrong and his decision of speedy descend of the aircraft led the plane to crash on the ground, after colliding with the treetops, in a nearby town only a few miles away from the runway. After the crash, the plane caught fire and lead to the death of 21 passengers and 3 crew members, including the commander and first pilot. Out of 33 people on board, only seven passengers and one crew member survived (Aircraft Accident Investigation Bureau & Swiss Confederation, 2004).

The major reason of the air crash was the cockpit failure that was due to the ignorance of the co-pilot and the commander on fast descent of the aircraft below the Minimum Descend Altitude (MDA). Commander’s complacency over his knowledge of the Zurich airport is what led him to misjudge the distance of the aircraft from runway and thus led him to descend below the MDA causing the air crash (Aircraft Accident Investigation Bureau & Swiss Confederation, 2004).

Reasons of Crash

The main reason that led to the air crash, as has been stated above, made the pilots responsible for the crash. Though the weather conditions were adverse, but the human error on part of the commander and the co-pilot were what led to the crash. The first element that added up to be a cause for this air crash is the inability of the pilot to successfully apply the VOR/DME approach. The pilot has shown major deficiencies in safely flying a plane in the past few years, especially in applying the modern aircraft flying techniques, which proved him incapable of flying the plane. Still the airline hired the pilot for this flight and did not take any adequate action to alter this discrepancy. Moreover, the unavailability of glideslope/localizer information along with the missing key terrain details in the approach chart led the pilots to maintain terrain clearance by reducing the planes altitude in steps, leading them to misjudge their distance from the ground (Aviation Safety Network, 2004).

Weather conditions, though were adverse led to poor visibility due to cloud cover, did not exactly contribute to the plane crash. The inaccurate data collected from the station nearby runway 28 led to the miscalculation of weather minimums and thus misled the pilots as they were unaware of what weather conditions awaited them. However, despite the warning of acute visibility of the runway given by the aircraft landing before flight 3597, the pilots continued to descend ignoring them. Moreover, there was quite a bit of ignorance on the part of co-pilot who did not notify the commander on his wrong decision to descend further even when he couldn’t spot the runway. This lack of teamwork and inadequate division of work led the captain to spent most the time spotting the runway looking out the window degrading their situational awareness. This led them to be unable to judge the proximity of the plane with the terrain. Furthermore, the captain deliberately reduced the altitude below 2390 feet and violated MDA which was thus the major reason leading to the crash. Moreover, the captain was fatigued as this was his fourth flight of the day and was unable to rest for an appropriate amount of time, thus affecting his cognition and perceptibility/understanding of the situation (Aviation Safety Network, 2004).

One technical fault which if have been removed would have helped avoid this accident is the existence of the basic GPWS (Global Proximity Warning System), which does not provide warnings of “terrain” and “pull up” to the aircraft in case it is below the MDA. These warnings would have helped the plane avoid the collision with the hill. Moreover, if the basic system was replaced with EGPWS (Electronic Global Proximity Warning System) which was available at the time, these warnings would still have been provided thus avoiding collision (Aviation Safety Network, 2004).

Survival Analysis

In order to survive an air crash, there are numerous suggestions and measures that could be taken. Many have in fact been suggested and implemented as well by the Federal Office for Civil Aviation and Crossair Airways. However, according to this accident there are a few safety measures that could help passengers survive a crash or help airplanes avoid the crash altogether.

The first safety measure that must be taken to avoid air crash is the construction of the air craft. It is possible to avoid an air crash by altering the structure of the aircraft, to make it less resistant to the collision or impact that it comes to during a disaster. The structure that makes initial contact with the ground or soil must be made and designed in a way that would lead to this collision minimizing the gouging and scooping of soil, thus leading to reduced accelerations and force levels and thus reduced friction and probability of aircraft catching fire and blasting. This means the outer structure of the areas of the aircraft that could gouge and plow must have a relatively flat surface increasing its tendency to slide over the impact terrain. Thought expensive, this could be very useful considering the fact that air crashes might still take place even after various security measures due to natural conditions (Simula & Pheonix, 1989).

Ancillary equipment, which is the removable equipment carried in the aircraft, must be retained during a crash as it might sometimes serve as a trigger to an aircraft’s hazardous crash. These equipments mostly include emergency equipments like oxygen bottles, aircraft subcomponents like radio and electrical equipment, survival equipment like life jackets and miscellaneous equipment like navigation kits. This can be done by providing these equipments with the integrated restraint devices to retain them during a survivable crash. Non-restrained equipment, which is not regularly carried on aircrafts, must be provided stowage space that is strong enough to hold these during a crash. For instance, a wheel chair of a passenger or an animal being carried on a cage must have a proper stowage space as these might prove to be hazardous and dangerous during a crash (Simula, 1989, vol. I).

These were some of the safety measures to be taken to avoid life loss or other damages during an air crash. To avoid an air crash altogether, the first thing that needs to be done is keep a check on the pilot schedules to make sure no pilot is overworked and fatigued while flying the plane. This was one of the reasons of this plane crash. Another measure that could be taken is making sure the pilot and the co-pilots selected have had a good knowledge and experience with the new automated planes and have a record of performing well flying these planes. Moreover, the co-pilot must have a minimum of 5 years of experience to be able to fly the plane, unlike this case where the co-pilot was an amateur. The performance of pilots must be monitored by looking into the criteria, regulations and procedures which govern the selection and conversion of pilots of aircraft with piston engines or turboprop propulsion systems to aircraft with jet engines or aircraft with modern equipment (Aircraft Accident Investigation Bureau & Swiss Confederation, 2004).

Another measure Federal Office for Civil Aviation must take is to examine the extent to which the standard flight procedures of Crossair require to be acclimatized. During a non-precision approach, it must be ensured that the MDA is set on the mode control panel instead of the go around altitude, which was the procedure followed by this airline at the time. The office must ensure the retrofitting of terrain alert and warning systems like EGPWS in bigger planes if they are possess basic GPWS systems. The approach sector of runways like runway 28 must be equipped with a minimum safe altitude warning systems which provide visual and acoustic warnings to planes in case they violate these minimum limits. Air Traffic Control regulations must thus include the regulations on warnings for the crews to follow (Aircraft Accident Investigation Bureau & Swiss Confederation, 2004).

So, these are a few safety and security measures that could help the aircrfafts survive an air crash or in cases where still an air crash happens to take place, some of the measures would help in the survival of maximum people travelling. Most of the measures that we have discussed here are according to the air crash of Crossair Flight 3597 and thus provides an insight on how this survivable crash could have been avoided.

References

Aircraft Accident Investigation Bureau & Swiss Confederation, SKYbrary Bookshelf. (2004). Final Report No. 1793 by the Aircraft Accident Investigation Bureau concerning the accident to the aircraft AVRO 146-RJ100, HB-IXM, operated by Crossair under flight number CRX 3597, on 24 November 2001 near Bassersdorf/ZH. Retrieved 22nd August, 2012 from http://www.skybrary.aero/bookshelf/books/989.pdf

Aviation Safety Network, Flight Safety Foundation. (2004). Accident Description. Retrieved 22nd August, 2012 from http://aviation-safety.net/database/record.php?id=20011124-0

Simula, Inc. (1989, December). Aircraft Crash Survival Design Guide-Volume 1: Design Criteria and Checklists. Arizona, Pheonix: U.S. Department of Commerce-National Technical Information Service.

SyedN07. (2011, April 22). Brand NEW! 2011 – Air Crash Investigations – Cockpit Failure – Crossair LX Flight 3597 [Video File]. Retrieved 21st August, 2012 from http://www.youtube.com/watch?v=oYDXQ-fCSyU.