The roar of an airplane during take-off is music to the ears of an aviation enthusiast. With the jet engines running on the maximum throttle, generating a huge amount of thrust, airplanes climb high and disappear into the skies. But is that force actually enough to have a person sucked into an airplane engine?
Yes, you can easily get sucked into an operating engine and it can be fatal. When an engine operates, the amount of air getting sucked though its intake can cause a low air pressure area in the surrounding areas and pull you towards it. If you’re standing close enough to an operating engine, you can get sucked in by the sheer force of the airflow.
Getting sucked into an engine is fatal and on the other hand, it is also a possibility in routine operations so what safety mechanisms are employed on the airports by the airlines to ensure the safety of operational staff?
Table of Contents
What Safety Procedures Are In Place to Avoid Accidents?
Safety procedures plan a vital role in ensuring that during maintenance or operations, personnel involved do not get injured in any way. Each airline develops its safety procedures based on the information provided by airplane and engine design organizations.
For example, in most airlines around the world, before starting an engine, the captain asks the ground crew to visually confirm that no person or equipment is present in the vicinity of the engine (the inlet hazard area) which can get sucked in.
Additionally, it important to ensure that no personnel or equipment is present around the engine exhaust as hot exhaust gases can even launch a human into the air and throw them at a distance.
Airplane engines also go through ground run-ups during scheduled maintenance. Unlike starting an engine before a flight, the ground run-up of an engine requires that the engine is given a specific throttle input higher than idle settings.
Therefore, the clearance areas which are the inlet hazard area and exhaust hazard area must be visually cleared and cones are placed to mark the boundaries of hazard areas are the engines.
High Power Runups
Another type of an on-ground engine run is high power run-up, or a power assurance test, which involves running an engine up-to its maximum throttle or thrust settings.
This engine run-up is done at specified areas at an airport as the exhaust hazard areas are quite large in this case. Special procedures are adopted to ensure that all personnel except those on-board, stay at a safe distance from the aircraft during these tests.
Many airports have special regulations for engine run-ups as well. For example, most airports do not allow an engine to start near a jet bridge due to the high concentration of ground service personnel and vehicles there. Additionally, many airports require that airline personnel place cones to mark hazard-areas around an aircraft whenever they are parked.
So, we have covered the inlet hazard areas and exhaust hazard areas. But just how big are they?
What is the safe distance to avoid getting sucked into an airplane engine?
Engine manufacturers need to identify the potential hazard areas around an engine where it is possible for personnel or equipment to get sucked in.
If you ever see an engine closely, it has markings in red color which are indicators showing the approximate hazard area around an engine. For an operating engine, the complete 180-degree sweep in front of the engine starting from the longitudinal center of the engine is considered an inlet hazard area.
The exhaust hazard area is, however, shaped like a cone in line with the airflow of exhaust gases.
The hazard areas differ in shape and size for distinct types of engine runs, such as engine start, engine ground run-up, and power assurance test.
The exact shape and size of these hazard areas are given by the manufacturer in Aircraft Maintenance Manual Chapter 05-20 or Chapter 71.
For example, for an Airbus A320 aircraft, the inlet hazard area is 14ft or 4.2m in front of and on the sides of the engine inlet.
What are the common airplane engine ingestions?
A human being getting sucked in an airplane engine is possible but quite rare as everyone involved in airplane operations understands these hazards. Also, all personnel operating on the apron are given continuous training to keep them informed about the risks they are working with.
Even if personnel is not getting sucked into engines, they still get their fair share of ingestions of FOD (Foreign Object Debris) on the ground or runway.
FOD can range from small stones to large equipment such as toolsets, etc.
On apron area (ground) airplane engines can ingest FOD quite easily which can damage the fan or compressor blades of an engine.
Although damage caused by FOD can present issues in flight as it happens on the ground, most engine troubles can be identified on the ground before the airplane gets airborne.
Bird Strikes
Bird strikes are also quite common near airfields, but a bird strike only becomes dangerous when it is ingested into the core engine.
If multiple birds or bird of larger size gets sucked into an engine core, they can cause serious engine problems including inflight shut-down of the engine.
We all remember Sully and the Hudson miracle which demonstrates just how crucial these events become.
Can a ground handling vehicle get sucked in an airplane engine?
Ground handling vehicles operating around an aircraft can get sucked into an airplane engine. Although they would not be able to go through the engine, they can be pulled towards the engine and hit the inlet cowl and engine fan blades.
There have been several instances of airplane engines pulling in catering vehicles or cargo pellets, etc. It is therefore important that traffic cones be places around the airplane engines so that ground handling vehicles can avoid getting too close to an operating engine.
What happens when you try to stand behind an airplane engine?
Standing behind an operating engine is not a clever idea and I am sure we are all smart enough not to try it.
But if this question pops up, for an engine operating at high throttle, consider the effect of hot gases with a temperature greater than 600o Celsius, blowing at you at a velocity above 1000kph, would have. They are quite likely to blow you away and one can experience serious burns on the skin.
For this reason, the high power ground run or the power assurance test of jet engines is done at specified distant planes on airports with a safety barrier/ wall on the aft side of the airplane. This way, exhaust gases are redirected and do not cause any damage to personnel or property.
Furthermore, the safety procedures of engine run-ups also include communication and permission from air traffic control so that they can warn other vehicles operating in the vicinity to be cautious.
Conclusion and Summary
- Modern engines, with their high thrust ratings, can suck in objects much heavier than an average individual especially when they are operating at higher throttle or thrust settings. Due to the low-pressure area formed in the surrounding area of an engine, someone can get sucked in even if he/she is standing on the side of an operating airplane engine.
- It is therefore important to take necessary safety precautions and respect the procedures implemented on airports to avoid such accidents.
- In addition to the inlet hazard area, the exhaust area of an airplane engine is also dangerous owing to high-velocity hot gases being blown out.
- The instructions given in the maintenance manual of each aircraft provide detailed information regarding the exact dimensions of hazard areas and any additional safety procedures which must be followed.
Now that we know the risks involved in day-to-day airplane operations, I think we can appreciate the personnel who make safe air travel possible for us all.
Happy flying!
Recommended Course!
