Why run out of fuel before landing. Question to British Airways Captain: When do planes dump fuel? Which version do you think is the most likely?
Is it true that planes dump fuel before landing?
The most interesting thing is that today the planes practically do not dump fuel. Previously, aircraft had such a supply of fuel that was designed only for flight, in case of an unplanned landing, the aircraft either circled over the airfield to burn out the remaining fuel, or dumped it so that ignition did not occur during landing. Now progress has moved forward. Now a special powder is thrown into the fuel tank, which simply makes the fuel non-combustible and can not be dumped.
Today, such a phenomenon as fuel dumping is practically not found in the flight practice of civil aviation pilots - on the contrary, they are rewarded in every possible way for fuel economy - this is a business today and only in the event of an emergency will pilots dump fuel. If the fuel is constantly dumped, then the ecological catastrophe will be fast on Earth.
Airplanes do not jettison fuel before landing.
They have no reason to do this if everything goes according to plan and the landing is not emergency.
But if you need to land urgently, an emergency situation has arisen, then there are rules that the crews of air vehicles are forced to adhere to, and under which the aircraft must be landed after dumping excess fuel.
Yes, this really happens in the event of an emergency landing. Once there was a rowdy passenger on board, whom the flight attendants could not calm down in any way. It threatened the safety of passengers and cabin crew. And the pilot decided to land the plane. The landing was made urgently at the nearest airport, but there was a lot of fuel left in the tanks. As a result, the pilots had to dump fuel. The brawler was arrested after the flight, and the airline sued him and collected a large amount of money. The same can happen with a sick passenger on board or an emergency on board where an emergency landing is necessary.
Fuel is dumped only during an emergency landing immediately after takeoff. Kerosene costs decent money, so no one will dump it unless absolutely necessary. A black mark usually does not occur during landing, but during takeoff, when the engine is running at maximum power in afterburner mode, a trace is left by soot from unburned kerosene residues.
An aircraft dumps fuel if it is forced to make an emergency landing, as there is a risk of an explosion. The more fuel left in the tanks, the stronger the explosion can be in case of failure. If the landing is unplanned, but not emergency, then the fuel is burned.
Here Sergey Rakitin quite rightly answered that the plane dumps fuel only in case of a forced landing, immediately after takeoff or somewhere in the middle of the way, but even then, if the situation allows, then kerosene not reset, and maximally produced to a safe weight. Emergency reset is done only in the case when the aircraft, for some emergency reasons, cannot fly in circles while running out of fuel.
Landing a plane with a lot of fuel on board is risky. The flight route and refueling of the aircraft are calculated taking into account that there is enough fuel to reach the alternate airfield and that after landing at such an airfield there is still approximately one to three tons of kerosene left (this is for large liners).
In the event of an emergency fuel dump, behind the aircraft, not a black trace, but a white one, will be visible. The black trace is, as Sergei Rakitin writes, just soot and soot from kerosene.
Planes dump fuel only in the event of an emergency emergency landing to avoid fire. In some cases, if the situation permits, the crew continues flying on purpose in order to use up the maximum fuel supply. And no one dumps fuel on purpose.
During emergency landings, fuel dumping is necessary. And a reset is made only in the case when it is impossible to reduce the amount of fuel simply by producing it. Planes just fly in circles, running out of fuel. If this is not possible, then reset at high altitude.
By reducing the amount of fuel, the crew of the aircraft reduces the possibility of an explosion during an emergency landing and, accordingly, a fire.
MINSK, May 6 - Sputnik. The actions of the crew of the Sukhoi Superjet 100 aircraft and ground services made it possible to avoid even more casualties among passengers, Honored Pilot of Russia Vladimir Romanenko said in an interview with Sputnik.
On Sunday evening at Sheremetyevo airport, after an emergency landing, a plane belonging to the Aeroflot airline caught fire. The liner was supposed to fly to Murmansk, but was forced to return to the air harbor. The fire on board killed 40 passengers and one crew member.
Why did the crew not drain the fuel
"Superjet belongs to the class of small-body aircraft, and it does not provide for fuel draining in the air. This procedure, like for all short-haul aircraft, is possible only on the ground," Vladimir Romanenko said.
In his opinion, "all that the pilots of the liner could do in such a situation was to burn fuel while circling over the airfield." In emergency cases, aircraft of this class are allowed to land in excess of the maximum landing weight. For long-haul aircraft, a significant excess is unacceptable, since the landing gear will not withstand.
For short-haul liners, such landings are allowed subject to compliance with the requirements for reloading and a mandatory subsequent technical inspection. In view of the fact that the crew had no radio communication, the development of fuel under the guidance of dispatchers was impossible.
"Thunderstorm, lightning flashes ... There are other aircraft in the vicinity of the airfield, in the immediate vicinity. Since the crew could not receive dispatcher commands, the PIC (aircraft commander - Sputnik) decided to land," Vladimir Romanenko explained. "They made the right decision."
Caught a "goat"
At the same time, the vertical speed was high, and "therefore, we got a" goat "(the term for" rebound "of the liner from the runway after touching the landing gear - Sputnik). Apparently, not all aircraft control systems worked correctly when landing in manual mode .
"The crew could not land and went to the second circle. "Shooted", as you can control the plane and feel it, and tried to land again, - Vladimir Romanenko explained the actions of the crew. - The attempt was unsuccessful, perhaps a gust of wind interfered. Like me I assume that the matter is in the aircraft's inadequate response to the crew's control actions.The liner did not behave as the crew expected and "sank".
The footage from the crash site at Sheremetyevo shows how passengers leave the burning plane along with hand luggage: bags and even suitcases. Obviously, this slowed down the evacuation process.
According to an experienced pilot, delaying passengers with suitcases is creating even more congestion on the plane. “Moreover, they opened the luggage compartment, which led to an even stronger fire in the tail section,” he drew attention.
Crew halved evacuation time
At the same time, we must pay tribute to the ground services: the firefighters worked "five", the expert has no doubt.
“They could not stand along the runway, there is no reason for this. Being in the starting mode, the fire brigades calculated the place where the liner would stop,” explained Vladimir Romanenko. it turned out ... Where to go: full tanks of fuel ... Well, at least these passengers were saved.
“If it weren’t for the crew, which reduced the time for evacuating passengers by almost half of the standard, at best, only the crew itself and five or six passengers would have survived,” Sputnik’s interlocutor summed up.
Question A: I've always wondered why emergency landing planes don't dump fuel these days. Indeed, in a crash, many people can survive thanks to modern safety equipment on board the aircraft, but die in the fire that follows the crash or suffocate from carbon monoxide.
Answer: Do you think that pilots are aware of the inevitability of the crash and do not try to avoid it until the last second. This is wrong. It is worth remembering that not all aircraft are equipped with an emergency fuel dump system.
Even if a crash occurs, a much smaller percentage of passengers die from burns or smoke than most publications claim. According to NTSB statistics, passengers who are involved in a major plane crash are much more likely to survive.
Question: What happens when a pilot dumps fuel? Does it dissipate and then evaporate? And where is it usually prescribed to do this, over land or over water?
Answer: Yes, if necessary, the fuel is discharged through a specially designed nozzle, which disperses it into tiny drops. The dumping of fuel itself is allowed only in specially designated places. To minimize the impact on residential areas, we must also not harm people on the ground.
Question: In the past, almost all aircraft models were equipped with an emergency fuel release system, but this system is usually not present in modern aircraft models. Why did engineers abandon this safety system and does it have worthy alternatives in modern aircraft?
Answer: Modern aircraft, unlike their predecessors, are equipped with an overweight emergency landing system, which gives pilots the opportunity not to make an emergency dump of excess fuel. After such a landing, the aircraft undergoes a thorough check to eliminate the problems that have arisen and to make sure that the aircraft is fully operational and ready to fly.
