Solved

Use of flaps during approach and landing phase of a flight

Posted on 2013-06-30
4
423 Views
Last Modified: 2013-07-07
I wanted to check the following question that I got wrong. My understanding of the use of flaps is that on approach the descent angle is steeper (improving forward vision), the stall speed is reduced and a slower groundspeed (decrease in aircraft momentum) which will shorten the landing run compared to a clean configuration.

"Why is full flap selected during the approach and landing phase of a flight?"

A- the safe flying speed is increased and a flatter approach path is achieved which improves forward vision.

B-the approach speed is reduced and a steeper approach path flown which improves vision.

C-the approach speed is reduced and a flatter approach path flown which improves vision.

I picked answer B but the book has answer C. I have attached the extract of the explanation from the book(EPP14C).

I would agree that for "take off" that the use of flaps helps reduce the ground run getting the aircraft into the air sooner(take off at lower IAS) than a clean configuration and the use of flaps for take off provide a flatter angle (reduce the initial angle of climb).

Any thoughts would be appreciated.

Cheers,

Ross
image.jpg
0
Comment
Question by:ross13
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
4 Comments
 
LVL 24

Accepted Solution

by:
aadih earned 167 total points
ID: 39288133
I believe you are correct, in general:

"During the landing phase, flaps contribute to a steeper descent angle by increasing the parasite drag produced by the wing. A slower approach speed and a shorter landing distance (as a consequence of reduced stall speed and increased aerodynamic braking) is also achieved by an appropriate deflection of wing flaps."

[Note: It also depends on the airplane model. On some airplanes, flaps cause a decrease in aircraft pitch angle which improves the pilot's view of the runway over the nose of the aircraft during landing (book answer). So, it depends on airplane, flap type, and location of the wing.]
flaps.jpg
0
 
LVL 84

Expert Comment

by:ozo
ID: 39288276
Are you confusing the pitch angle of the aircraft with the angle of the approach path?
0
 
LVL 37

Assisted Solution

by:TommySzalapski
TommySzalapski earned 166 total points
ID: 39288385
I would say the answers are worded poorly
flatter approach path flown which improves vision
It is not the flatter approach path which improves vision, it is the flatter pitch altitude that improves vision (as the book states in the image).

Using the flaps does both flatten approach path and improve vision but the flatter approach path does not directly improve the vision as C implies (although they are related). C is still the most accurate since B says "steeper approach path" which is wrong.

The flaps increase the lift generated which is what makes the approach path flatter. The flaps also allow the pitch to be flatter (the nose doesn't point up as high) so the vision is improved.
0
 
LVL 84

Assisted Solution

by:ozo
ozo earned 167 total points
ID: 39288596
flaps increase the lift
they also increase drag, which would tend to steepen the glide slope angle, so pilots often compensate by increasing thrust.
0

Featured Post

Free Tool: SSL Checker

Scans your site and returns information about your SSL implementation and certificate. Helpful for debugging and validating your SSL configuration.

One of a set of tools we are providing to everyone as a way of saying thank you for being a part of the community.

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
Error in calculation 2 100
Math "Stumper" - What is a 1% incremental improvement in AVAILABILITY/RELIABILITY WORTH? 14 85
Graph Function 6 120
Linear algebra 3 73
Foreword (May 2015) This web page has appeared at Google.  It's definitely worth considering! https://www.google.com/about/careers/students/guide-to-technical-development.html How to Know You are Making a Difference at EE In August, 2013, one …
When we purchase storage, we typically are advertised storage of 500GB, 1TB, 2TB and so on. However, when you actually install it into your computer, your 500GB HDD will actually show up as 465GB. Why? It has to do with the way people and computers…
Finds all prime numbers in a range requested and places them in a public primes() array. I've demostrated a template size of 30 (2 * 3 * 5) but larger templates can be built such 210  (2 * 3 * 5 * 7) or 2310  (2 * 3 * 5 * 7 * 11). The larger templa…
I've attached the XLSM Excel spreadsheet I used in the video and also text files containing the macros used below. https://filedb.experts-exchange.com/incoming/2017/03_w12/1151775/Permutations.txt https://filedb.experts-exchange.com/incoming/201…

752 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question