When an aircraft is preparing to depart from its gate, a small but powerful tug assists it in the process of pushing back from the stand and towards the taxiway. While we passengers do not often take the time to fully examine what is going on the apron, the carefully choreographed chaos is directed almost entirely by tugs.
But would it not be significantly more simple if tugs were not involved in the aircraft departure process at all? Aircraft can move on their own, so should they not just drive themselves from the gate, onto the taxiways and to the runway?
Many may see this question and believe the answer lies in the fact that aircraft do not have a reverse gear, but this is, in fact, not the case whatsoever. At any time, an airliner can easily move backward on its own power, but this would cause a whole host of other issues. In this article, we will take a deeper look at airport maneuvering systems and attempt to identify why aircraft do not use their reverse gear.
Noise pollution
The concept of thrust reversal is not foreign to any pilot or aviation enthusiast and is one of the many reasons why aircraft are still extremely loud upon landing. When touching down, a jet will often direct thrust forward rather than backward, to bring the aircraft to an efficient stop.
On short runways or during icy conditions, the increased drag created by thrust reversal is essential to ensure that jets can land safely. Thus, in an industry that is dominated by low margins and reduces costs at any attempt, why do aircraft pay for tugs when their planes could push back on their own?
According to Amsterdam’s Schipol Airport (AMS), the main reason why this is rarely attempted stems from the extreme noise generated by aircraft engines to reverse thrust. There is simply no reason to have jet engines roaring so close to the terminal or add to the massive noise pollution created by an airport.
Additionally, reversing thrust involves using incredible amounts of fuel, much as taking off or landing does, and, as a result, would increase aircraft costs significantly more than the nimble tug does. However, in an emergency circumstance, a pilot is free to remove his aircraft backward using reverse thrust if no other option is available.
Ingestion danger
As the apron is an incredibly busy place, operating jet engines with reverse thrust could be incredibly dangerous. Not only could parts or debris lying on the ground be ingested into engines, but individuals working in the area might be seriously injured in tragic accidents.
While unrelated to reverse thrust, multiple accidents in 2023 led to the death of ground workers involving engine ingestion. In June, a ramp worker was ingested into a jet engine at San Antonio International Airport (SAT), an incident in which the worker sadly lost his life. There is ultimately no need to add the unnecessary danger of reverse thrust to the chaos of the apron.
Source: simpleflying.com