Questions tagged [descent]

Mode of flight when an aircraft's altitude is decreasing.

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8
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2answers
752 views

What is the minimum altitude over Egmond aan Zee when landing at Schiphol?

I live in Egmond aan Zee which is about 36 km flight distance from Schiphol. It seems that aircraft fly over Egmond when there is a southerly wind so they can make a landing approach to Polderbaan ...
4
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1answer
309 views

When does a passenger plane leave the cruising phase?

I have Flightradar24 data here. Which are in the following structure. ...
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2answers
172 views

What is the relationship between drag and sink rate?

I was just brushing up on basic aerodynamics and I have something I want to clarify about flying in the region of reverse command. I went up in my 172 the other day and noticed the following while ...
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2answers
132 views

PA/APV Glidepath Descent and Obstacle Clearance Slope's lowest point determination

I am studying the US Terminal Instrument Procedures manual (TERPS) and as I was skimming through the guidelines about Sloping Obstacle Clearance Surface, I came across the image below from section 2-1-...
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1answer
352 views

Why would a plane drop 14.000 ft mid flight?

Just noticed American Airlines flight 221 dropped 14.000 ft mid flight today. Curious, what could have caused this? Here are the flight details.
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1answer
281 views

What would the altitude profile for a typical airline flight look like?

It's hard to appreciate an aircraft's rates of change in altitude, in particular with respect to its travel through the mass of air, rather than over the ground, since the latter is affected ...
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7answers
912 views

Is it possible to fly 'in neutral'?

Sometimes, when I am driving, I knock the car 'out of gear' or set the stick to the neutral position, to save fuel. This is most easily done when cruising down a hill or when you have some good speed ...
3
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4answers
1k views

Why would the Speedbrake be required for such a long time on approach? [duplicate]

As far as I was aware, the Speedbrake is designed to slow the aircraft down. On landing, I do understand why they are required. Once the aircraft has hit the tarmac, they are deployed to 1) slow the ...
-1
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1answer
300 views

What is the speed and inclination angle of a commercial plane during descent?

I have a question based on flight track logs on https://flightaware.com. In one of the logs I'm looking at, it says that at time 08:16:15 PM the altitude was 36,000 ft and plane speed was at 473 mph. ...
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2answers
364 views

Does MMO (limiting Mach number) assume any maneuvering limits?

This answer to a question about emergency descents notes: [Y]ou can accelerate descents by banking the aircraft into a turn. This allows you to increase angle of attack, thus increasing drag to ...
2
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1answer
1k views

How fast can a large passenger jet descend and slow from cruise to emergency land? [duplicate]

On 17th April 2018, Southwest 1380, a Boeing 737-700, was cruising about FL320 when it suffered a catastrophic failure to engine 1. It then took 5 minutes to descend to 10,000 feet, and I noted from ...
4
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1answer
2k views

How should I read these climb and descent profile notations?

I use a tool called SimBrief to build virtual flight plans for a desktop flight simulator. As I've been getting more familiar with procedures, I've also been exploring more advanced settings in the ...
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2answers
6k views

How do we calculate top of descent (TOD) in flight? [duplicate]

What is the in-flight trick? I know how to calculate it in theory, but how can I calculate it fast? For example, I know I can use this formula for calculating the rate of descent: [ground speed + ...
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2answers
400 views

What are the negative associations with Continuous Descent Approach?

According to this Wikipedia article: Due to the negative association with the term CDA,[citation needed] new procedures introduced at LAX and other US airports are instead called optimized ...
4
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2answers
1k views

What is the typcial descent rate of a helicopter?

I'm not a pilot, just asking out of curiosity. What is the typical descent rate for a helicopter when landing? I found the answer of 300 feet per minute on the web, but I want to confirm this. If this ...
3
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1answer
283 views

What effect do slats have on descent rate?

During descent, assuming the same speed and idle thrust, is the rate of descent greater in a clean configuration or with slats?
26
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3answers
4k views

Do airline pilots use this high-speed, high-drag technique for losing altitude?

This question and another more recent one got me thinking about this. Years ago on my MEII checkride the DPE showed me a technique for losing altitude on final when the aircraft was high. Typically, ...
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4answers
1k views

Is there any disadvantage to slipping as a way to lose altitude?

I learned how to slip during my powered training as a way to lose altitude when too high and, of course, a way to track the runway center-line during a crosswind landing. Quite a bit more emphasis ...
5
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1answer
720 views

How far from the runway should a small plane start its descent from 5000ft?

I don't fly, don't have a clue. But one of the main characters in my book DOES: it's a Cessna 152, just him at 14 stone and a couple of small bags, all conditions are perfect and he's flown from about ...
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0answers
108 views

How does a commercial jet descend? [duplicate]

When landing a modern Jet such as the Boeing 737, what is the primary source for descent? The elevators or gravity(from reduced airspeed) or a combination of both? Is the glide path angle of descent a ...
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3answers
3k views

When is the descent clearance requested from ATC?

Is there a rule / Standard Operating Procedure as to when request the descent clearance during cruise flight? Something like one minute before reaching the Top of Descent point?
4
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2answers
462 views

Why doesn't the flight path angle increase beyond a certain angle even if the angle of attack is increased?

From level flight, when the angle of attack is increased the flight path angle increases (the aircraft starts to climb). What causes the aircraft to stop to increase its angle of climb (angle between ...
10
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4answers
12k views

What is the descent rate in emergency situations?

I fly a plane at 40000 feet. There is a sudden depressurization; what is the maximum vertical speed I can keep to come back at a proper altitude? Is this speed different for different emergency ...
15
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2answers
7k views

Why is a 3 degree descent angle used?

Following on from this question on the descent rate formula. It appears from the answers and comments that a 3 degree slope is pretty standard across the board. I would like to know why a 3 degree ...
3
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3answers
9k views

What is the maths behind the descent rate calculation?

The descent rate calculation states that descent rate is calculated by 'groundspeed / 2 * 10'. Another document stated that the ground speed should be multiplied by 5 (or more accurately 5.2) to ...
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4answers
17k views

How do planes descend for landing?

I fly occasionally on a pretty short route on a turboprop (DHC-8). When the airplane descends for landing, I can look through the window and see the ground below getting closer over time. However I ...
17
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1answer
3k views

How frequent is the use of spoilers during descent?

Having flown a number of flights as a passenger recently, I observed that: Roughly 50% of pilots used spoilers above FL180 Almost everybody used spoilers to pass the 10,000 feet / 250 knots mark ...
3
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2answers
561 views

Is the separation distance between two aircraft approaching an airport the same under CDA and Non-CDA scenario?

I'm working on a project that investigates Continuous Descent Approach (CDA), the procedure by which an aircraft approaches an airport for landing by descending continuously from cruise altitude with ...
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5answers
2k views

What happens during a powered descent?

I was having a discussion with my friend about equilibrium condition in flight: Scenario: While going in straight and level flight, say I reduced my airspeed by 30 mph. At the same time keeping the ...
5
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2answers
592 views

What is a mushing glide?

Source: Wolfgang Langewiesche - Stick and Rudder; An Explanation of the Art of Flying Why is it called a mushing glide? In this glide, does the aircraft point its nose less (or more?) steeply? How ...
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4answers
1k views

What does this statement about steep descent mean?

Source: Wolfgang Langewiesche - Stick and Rudder; An Explanation of the Art of Flying In the first chapter the author mentions, in a glide, if you want to descend more steeply, you want to want to ...
2
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1answer
2k views

How does the FAA compute the values in TPP's Climb/Descent Table?

The inside back cover of the FAA Terminal Procedures Publication contains a table headed “CLIMB/DESCENT TABLE,” excerpted below. Source: FAA, p. 19 How do required ascent or descent ...
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4answers
9k views

What is the difference between the Maximum Glide and Minimum Sink ratios?

In this comment a brief explanation is made of the differences between Max Glide Ratio and Min Sink Ratio: Sink rate is how much altitude you lose over time, for example, how many feet per second. ...
10
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2answers
593 views

Why isn't the point you begin descent part of the flight plan?

In This question there is discussion about how to determine when to start the descent from cruise. There are several factors at play and it is usually calculated for maximum fuel performance. Would ...
6
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1answer
146 views

What are the FAA regulations concerning controlled descent of a light payload?

I'm part of a High Altitude Ballooning club. Our main goal for this year is to achieve controlled descent of our payload. We plan to use Magnus force cylinders to go about this. I have found nothing ...
9
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1answer
919 views

When can I descent below the MDA if the approach light system does not have red terminating bars?

Specifically, I'm a little confused about Sec 91.175(c)(3)(i) which states: The approach light system, except that the pilot may not descend below 100 feet above the touchdown zone elevation ...
6
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4answers
4k views

What is the relation between aircraft descent rate and speed?

I am an ATCO working in India. I am trying to understand why an aircraft's rate of descent increases, when its speed increases. I am particularly interested in how it relates to jet engine aircraft. ...
4
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1answer
205 views

Is it currently feasible to glide airliners from cruise level to ILS glideslope (CDO)?

Is this possible for some airports to perform full continuous descent operations (CDO), gliding at idle thrust from top of descent to glideslope interception. (source: Lubo Mitev's Blog) LAX and UK ...
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4answers
1k views

During which part of the flight the effect of air resistance is more important?

Her teacher asked this question to my niece (8 years old)? However I couldn't find a solid answer either. In which part of the flight, the effect of the air resistance (drag) is more important? ...
6
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2answers
1k views

Are there certification requirements for an emergency descent?

In case of emergency, an aircraft may have to descend very quickly. Is there some performance (L/D ratio with full spoilers, descent rate, ...) to be proven in the certification process for such ...
18
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6answers
44k views

What is the normal descent rate for airliners?

A few days ago I was on a flight from SFO to AUS (Airbus 320) and I was shocked by the steep angle of descent into AUS. I have been on over a hundred commercial flights but I've never experienced such ...
16
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4answers
27k views

What is a rule of thumb for when to begin a descent?

What rule of thumb would you use for your airplane insofar as how far from your destination you would begin your descent given an expected straight-in approach and landing in no-wind conditions and no ...
10
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4answers
6k views

Is the descent performance of the PMDG 737-800 accurate?

I often fly the PMDG 737-800 (with winglets) in my home simulator and most of the time, I find it hard to slow the aircraft down for landing when I descend. Most of the time, I need to deploy the ...
18
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4answers
30k views

Flight Level Change or Vertical Speed - When to use it?

I've heard that some pilots have this difficulty to determine the correct use of both features. So, which is the difference between using the vertical speed, instead using the flight level change ...