48
votes
Is it practical to intentionally stall an aircraft to execute a fast, controlled descent?
It isn't practical for a number of reasons:
Intentional stalls are inherently dangerous. Stall-spin accidents are a major cause of accidents, stall recognition and recovery are taught specifically to ...
- 52.8k
35
votes
Why did my plane descend nose down?
Nothing out of the ordinary here. You probably arrived at the airport a little bit earlier because ATC allowed your plane to go directly to the runway instead of taking a longer route (as confirmed by ...
- 12.7k
28
votes
Why did my plane descend nose down?
According to FlightRadar24 here:
at one point your flight was descending at more than 4000 feet per minute. This is a bit faster than usual, especially for the (relatively) low altitude you were at ...
- 14k
26
votes
Accepted
Why does an airliner have a shallow descent when heavier, opposite to gliders with ballast?
If you can forgive my limited Paint skills:
It's the variable/constant speed that makes the difference.
Weight changes endurance (time to ground) and not range (distance to ground) if speed is ...
- 7,925
26
votes
Why did my plane descend nose down?
The economics of descent planning
Normally the pilot wants to descent in an economic manner and also try to keep passenger comfort in mind. Let's start with the "economic" descent: An ...
- 1,073
25
votes
Accepted
How frequent is the use of spoilers during descent?
Very frequent.
Modern airliners are certainly fairly slippery, but it's not so much that they're super-gliders that we can't wrestle down onto the ground.
It's more a function of busy airspace than ...
- 10.4k
25
votes
Do airline pilots use this high-speed, high-drag technique for losing altitude?
Airline pilots certainly do use gear/flaps/spoilers to descend more quickly if needed. However, SOP typically requires an approach to be stable upon reaching a certain altitude on the approach. This ...
- 71.8k
22
votes
Accepted
Is it practical to intentionally stall an aircraft to execute a fast, controlled descent?
You don’t need a new technique
You don’t normally stall jetliners. And in a crisis the last thing you want to do is learn a new technique.
Besides, they already have a trained practice for descending ...
20
votes
Accepted
What is the difference between the Maximum Glide and Minimum Sink ratios?
Glide ratio is the ratio of the distance a glider can travel horizontally to the altitude lost in transit. For instance, if a glider can travel 40 miles horizontally while losing one mile of altitude, ...
- 931
20
votes
Is it practical to intentionally stall an aircraft to execute a fast, controlled descent?
Normally, a stall and controlled flight are mutually exclusive.
That AF447 would descend as it did has to do with the relaxed static stability of the A330 and its rear cg location as well as the ...
- 228k
18
votes
How can I communicate an emergency de-pressurization descent to the cabin as a passenger?
A couple of things that get drilled into you in first aid or emergency response training is 'if you aren't part of the solution you're part of the problem', second is 'don't become a casualty.' In ...
- 52.8k
18
votes
Accepted
Are there aeromedical reasons to avoid too-rapid descent in hypoxia?
There are no aeromedical reasons to descend slowly due to hypoxia.
Also, the controller did not know for certain that the pilots were hypoxic due to a loss of pressurization. All the controller knew ...
- 37.3k
17
votes
Accepted
When is the descent clearance requested from ATC?
Whether there are any formal policies for when to request descent will depend on the airline. However, I doubt formal procedures are established, since it should be pretty obvious to pilots when to ...
- 35.7k
16
votes
Accepted
Do airline pilots use this high-speed, high-drag technique for losing altitude?
I actually got asked a similar question on a checkride two weeks ago. Right after I was asked to demonstrate an emergency descent through a hole. I heard the talk about the advantages of the ...
- 17.7k
15
votes
Accepted
How do planes descend for landing?
If the pilot reduces the airspeed while he increases the rate of descent, you will not notice any change in pitch attitude when the aircraft descends. With jets you should be able to hear a change in ...
- 228k
15
votes
Accepted
How can I communicate an emergency de-pressurization descent to the cabin as a passenger?
I’ve been a passenger on a plane in an emergency depressurization.
The first thing to realize is that everything happens amazingly fast. Even as a (GA) pilot myself, it was almost over before I even ...
- 27.5k
15
votes
Why would the U2 descend more quickly with its engine on than off?
From this the engine was used to extend "everything" to create drag and was only kept at idle power. 23 minutes was the typical descent time, not two hours, which went up to an hour if ...
- 18.8k
14
votes
Is it practical to intentionally stall an aircraft to execute a fast, controlled descent?
It is smarter to roll onto your side and maintain unstalled flight, executing a emergency spiral descent. G loads on the wings are much lower as there is no need to maintain altitude, only to control ...
- 18.7k
14
votes
How can I communicate an emergency de-pressurization descent to the cabin as a passenger?
Best thing you can do is remain calm, and let the trained personnel handle the situation.
Panic is a state of mind impenetrable to reason, and you being a random person amongst passengers will ...
- 26.7k
13
votes
Why would a glider have water ballast? If it is trying to stay aloft without an engine, wouldn't it be better to be as light as possible?
I'm tuning in more than 3 years late because I'm not fully satisfied with the answers here. Yes, Lnafziger, when you want to stay up as long as possible, the plane should be as light as possible. But ...
- 228k
13
votes
Accepted
Why is a 3 degree descent angle used?
Basically, it's a combination of historical significance, passenger comfort, and ease of mental calculation.
Historically, before aircraft were pressurized a rapid descent would be uncomfortable for ...
- 31.1k
13
votes
How far from the runway should a small plane start its descent from 5000ft?
For a comfortable decent you generally want to come down at 500 Ft/Min on the Vertical speed indicator. The 152 is doing about 95Kts over the ground (assuming no wind). So you are covering about 1.5 ...
- 100k
13
votes
Accepted
Why would the Speedbrake be required for such a long time on approach?
There are two reasons I can think of off the bat:
Its possible the controller asked them to hold a slow speed due to increased traffic ahead. The brakes may have been deployed to match the speed ...
- 100k
12
votes
Why would a plane drop 14.000 ft mid flight?
I looked up the flight on Flightradar24.com. The descent starts at 16:10 UTC and ends at 16:29 UTC, going from 38.000 feet to 24.000 feet. So, the aircraft descended 14.000 feet in 19 minutes.
14....
- 8,942
12
votes
What is the minimum altitude over Egmond aan Zee when landing at Schiphol?
Approaches into Schiphol are usually vectored by ATC during the day (see below for night operations). This means the controllers are giving instructions to pilots depending on the current traffic, ...
- 53.5k
12
votes
Are there aeromedical reasons to avoid too-rapid descent in hypoxia?
You could say there is a "technical" aeromedical reason for descending slowly, not related to hypoxia directly, but you shouldn't be flying at all if it exists and there's no way a ...
- 125k
11
votes
Why is a 3 degree descent angle used?
Descent is a matter of managing the aircraft's energy budget.
To descend, the aircraft must shed all its potential, and big part of its kinetic energy. Pilots reduce engine power to minimum to stop ...
- 56.1k
11
votes
Why would the Speedbrake be required for such a long time on approach?
Those are spoilers...not speed brakes. They do increase drag, but their primary function is that they kill lift. They allow the aircraft to lose altitude rapidly without pointing the nose downhill ...
- 1,308
11
votes
Accepted
Can the energy dissipated in a power-off descent be calculated and expressed in horsepower?
Horsepower = weight(lbs) * sink_rate(fpm)/(550*60)
It really is that simple.
Background
At a constant airspeed glide, kinetic energy isn't changing, only potential energy. So we know that all the ...
- 4,722
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