Pilots and airlines rely on aircraft tugs to perform towing and pushback operations for commercial, private and military aircraft with general ease. The traction design incorporated into aircraft towing equipment means safe movement and stops, even on snow and ice. But there are even more reasons why airlines rely on airport tugs. This article will explore why aircraft towing equipment is used so extensively at large and small airports in every corner of the world. Keep reading to learn more.
1. Aircraft Engines Can Create Hazardous Conditions
Aircraft towing equipment is typically used for the towing and pushback process to avoid some of the significant hazards posed by aircraft engines. When an aircraft's engine is activated, the thrust can create a high-speed wind that can easily cause damage to the airport terminal, surrounding ground vehicles, jetway, baggage and most importantly, ground personnel.
Suppressing the use of engines is especially important when towing a large aircraft, as their more powerful thrust capabilities can become exceedingly dangerous. Engine thrust can easily send any loose items airborne, turn the tiniest grains of dust into hazardous projectiles and create debris that can cause damage to multi-million dollar engines. Additionally, aircraft engines consume a great deal of fuel and generate extreme noise that can be harmful to ground personnel. Using a pushback tug for aircraft is simply a more economical and safer option than running the engines.
2. Aircraft Towing Is Easier for Maintenance Purposes
Towing and pushback tugs for aircraft are also used to make general maintenance easier for ground personnel. When an aircraft needs to be moved to a hangar for maintenance purposes or is not required for flight, the easiest way is to send an aircraft tug to the tow-in gate for transport. Aircraft towing frees up time for the airline, maintenance team, airport ground controllers and pilots who don't need to waste time getting the engines started. It's also not cost-efficient to start aircraft engines just to reposition an aircraft for maintenance purposes. Typically, ground personnel are trained to only need the aircraft brake system when towing a large aircraft.
3. Pilots Have Limited Visibility From the Flight Deck
Pilots do not have a clear view of the rear from the flight deck and thus rely on aircraft towing equipment for ground pushback when needed. Once the aircraft is perfectly positioned and far from the terminal tow-in gate and other vehicles, the airport tug is disconnected and the aircraft can use its engines and steering to move to the runway for takeoff.
4. Terminal Tow-In Gates Are Confined Spaces
Another common reason aircraft towing equipment is used in airports concerns aircraft safety from the taxiway to the tow-in gate. Aircraft towing from the taxiway occurs with significant time constraints, so pilots and ground personnel are under extreme pressure to navigate the aircraft quickly and efficiently. The tight confines of the terminal tow-in gate combined with the restricted view of the pilots generally always require a tow in order to arrive safely and on time.
Even though pilots follow taxi centerlines, aircraft with very large wingspans are often faced with the challenge of having adequate clearance. If an airplane connects with another aircraft or hits a gate terminal, it can cause significant damage, huge expenses and contribute to lost time for extra maintenance repairs.
Aircraft towing can prevent contact with other structures because ground personnel have much better visibility from the airplane tug. With the aid of ground personnel walking with the wings and tail, the airport tug driver can precisely position the aircraft to ensure it will not hit a structure, vehicle, person or another aircraft. In addition to this, the airplane tug driver is in constant communication with the pilots to ensure the aircraft will brake if an emergency occurs.
5. Pushback Tugs for Aircraft Are Required For Going In Reverse
Typically, most aircraft cannot move in reverse without the help of aircraft towing equipment. Planes are not designed with a reverse option that pilots can use for backward movement, so pushback tugs for aircraft are the only option when moving aircraft into hangars or away from the terminal building. This is because aircraft are not outfitted with gears or transmission for propulsion – power for movement is derived solely from the engines through thrust. When aircraft tugs are used to tow planes, an airline can maximize safety and optimize efficiency with on-ground operations.
While most commercial airliners with jet engines have thrust-reversing capabilities, they can only be used as additional braking power during landing. In addition to the problems mentioned above associated with using aircraft engines, reverse thrust also has what is known as the lowest-speed-of-operation limit. If reverse thrust is used below the speed of 80kts, it's very likely the engines will become heavily damaged.
What Vehicles Can Tow Planes?
Aircraft towing equipment mainly consists of two types of airport tugs: conventional towbar tugs and towbarless tugs.
Conventional Airport Tugs & Towbars
Some aircraft towbars are universal, meaning aircraft ground handling personnel can use them for multiple aircraft, but the size is a factor. For example, when towing a large aircraft, you would not want to use a portable universal towbar meant for a smaller jet. The towbar wouldn't be strong enough to move the mass of the aircraft and could easily warp and break. For this reason, most airport terminals are arranged for specific aircraft to use certain tow-in gates. This helps ground personnel to have the appropriate aircraft towing equipment close at hand for quick and efficient turnarounds.
Towbarless tugs work by reversing the tug up to the aircraft nose landing gear. The plane's front tires are then placed against a stop while a locking arm closes around the other side of the tires. Once it's secure, the airport tug will lift the landing gear tires off the ground. Then, the towbarless tug can easily move the aircraft around once the pilot has released the brakes.