Dear Capt Lim,
I have a few burning questions for you. I know you are very busy with dozens, if not hundreds of other questions from other visitors to your very popular website. But mine requires just a one-sentence answer or just a few figures to each of my questions.
I will be going to Macau, China with my wife for two weeks this Saturday, 16 December for my usual year-end holidays; sometimes we make 2-3 overseas trips a year. If you cannot answer immediately, I am willing to wait for your most illuminating answers.
The questions I wish to ask are:
1. What is the air distance between Kuala Lumpur LCCT and Macau Airport?
2. What is the distance between Kuala Lumpur LCCT and Hong Kong Airport?
3. What is the normal cruising speed of the Airbus A320?
4. What altitude does it normally fly?
5. What is the acceleration of the aircraft along the runway before lifting off?
6. What is final take off speed just as it lifts off the runway?
7. What is the time taken or the distance traveled along the runway before lifting off?
8. How long does it take to fly from KL to Macau?
Of course, questions 3-7 depend on the type of aircraft I will be traveling in, while the time taken from KL to Macau depends also a little on head or tail winds. An approximate time will do, as I will clock it myself.
Acceleration, initial and final speed, distance traveled, and time taken can all be calculated from Newton laws of motion if any of the 3 variables are known. So you need to give me just any of the 3 parameters for me to determine the 4th. But it is better for you to tell me all the (practical) answers.
I have actually theoretically determined the distance between Kuala Lumpur International Airport to Macau as 2482 km (1542 miles), and to Hong Kong as 2515 km (1569 miles). Hong Kong in the east is separated from Macau in the west by 58 km (36 miles). However, these are derived theoretically by spherical geometry applying the locations of their geographical coordinates. But I am unsure if these calculations and figures are correct?
What does your aircraft computer distance gauge say? It ought to be higher because the distance of the aircraft from the center of the Earth is more than from ground level, and having to ascend and descend as well. All these add to the distances, besides flight deviation sometimes, I guess?
Thank you for enlightening me with your expert knowledge to satisfy my curiosity about flight, navigation and aviation.
Hi Dr JB Lim,
My apologies for not being able to reply to your queries before you went off for your holidays as I was not feeling very well. Further, I was in the midst of relocating to another residential area and I had a lot of problem transferring my Internet account to this new location. Yes, I would also like to extent my apologies to many others who have written to me. The volume of questions (and repeated questions) is beyond what I can cope with now. However, I will reply to some of the questions whenever I have the time (hmm? answering FAQs was initially meant to be a hobby for me only!)
Below are the answers to your questions:
1. The distance between Kuala Lumpur International Airport and Macau Airport is 1356 nautical miles (1561 statute miles) as given by the airplane computer (based on their official position of latitude & longitude). Your answer of 1542 (I presume statute miles?) is 19 miles out. It doesn*t mean that it is wrong ? you probably used a different co-ordinate.
2. Again, the distance between Kuala Lumpur and Hong Kong Airport is out by 13 statute miles ? actual distance is 1582 statute miles as compared to your 1569 miles.
3. The normal cruising speed of the Airbus A320 is Mach 0.78 or around 450 knots (518 mph/833 kph) at the optimum cruising level. (The speed of sound or Mach 1.0 at sea level on a ?standard day? is 661 knots/761mph/1225 kph ? so it varies with altitude)
4. The normal cruising altitude to Macau is around 36,000 feet but it can vary between 31,000 to 39,000 feet depending on the air traffic flying along the Airway.
5. Do not be alarmed if I say the initial acceleration of the plane is slower than a racing car! The performances of the airplane engines are dependent on the environmental conditions and its weight. So I cannot be precise when answering your questions. It takes between 30 to 35 seconds to accelerate to 140-145 knots (164-170 mph) as compared to a F1 racing car that can achieve 0-60 mph in 2.7 seconds!
6. Again, the take off speed (we call it the rotation speed) is affected by the environment and configuration of the airplane. It can vary from 120 to 170 knots.
7. Time taken or distance traveled before lifting off the runway is between 30 to 35 seconds and the distance covered is around 2,500 meters.
8. The time taken to fly from Kuala Lumpur to Macau is around 3 hours and 35 minutes.
Yes, for all intent and purposes, some of the parameters given above are mostly approximate values only (to satisfy your curiosity :-)) as I do not know the actual weight of the airplane on the day you flew, the surface temperature, pressures, wind or the take off configuration.