Linked Questions

69 votes
10 answers
94k views

Why do jet engines get better fuel efficiency at high altitudes?

I'm told that this is true, but I can't imagine why. It seems like the fact that there is less air would make the engines less efficient... But that probably just shows how little I know about jet ...
Jae Carr's user avatar
  • 24.2k
52 votes
4 answers
12k views

Why are many jet aircraft designed to cruise around FL350-370?

If the flight distance permits, the B737-800 will cruise at FL350, the A320 a little bit higher... Flying at FL370. Photo: Live from the Flight Deck by GolfCharlie232 (reframed) Elements such as ...
mins's user avatar
  • 73k
67 votes
5 answers
43k views

What determines the maximum altitude a plane can reach?

What factors determine the maximum altitude for a plane? Is it limited by wing design, engine thrust, and so on? Is there a formula by which one can calculate the maximum altitude a plane can reach?
Vido's user avatar
  • 761
18 votes
5 answers
11k views

Why is there a difference between GPS Speed and Indicator speed?

I just played with flight simulator and noticed that the GPS shows different speed from the speed indicator in the cockpit. Also, GPS speed is higher than the Indicator. Any Idea why?
Super Hornet's user avatar
30 votes
6 answers
5k views

Why cruise at 7000' in an A319?

I was on a flight from Philadelphia (KPHL) to Boston (KBOS), after some delay and some change of route due to weather, the captain announced that we will be cruising at 7000' due to delays in the area....
Brice's user avatar
  • 452
30 votes
4 answers
22k views

How does wind affect the airspeed that I should fly for maximum range in an airplane?

I have heard that wind affects the actual airspeed that I should fly for maximum range in an aircraft. I understand that wind will not affect the airspeed that I should fly if I am looking for ...
Lnafziger's user avatar
  • 58.9k
11 votes
2 answers
24k views

How can I calculate the fuel consumption of an Airbus 320-200 at various loads?

I want to know: What is the fuel consumption of an Airbus A320-200 - 180 Seats, at 100% load factor for a distance of 2000 km? What is the fuel consumption of an Airbus A320-200 - 180 Seats, at 80% ...
user3551's user avatar
  • 119
7 votes
3 answers
3k views

What is the relationship between power and fuel efficiency?

We were having a discussion in our ground school that power will make the plane ascend or descend and that you use the stick for speed, forward for higher speed and back for slower speed. So does that ...
yankeemike's user avatar
6 votes
2 answers
1k views

Why do Vx and Vy coalesce at an airplane's absolute ceiling?

I'm struggling to figure out why that is the case. I'm trying to determine why the best angle of climb speed equals to best rate of climb speed at the absolute ceiling on airplanes.
nyorkr23's user avatar
  • 1,188
6 votes
1 answer
2k views

What is the peak of coffin corner called?

The converging point of Vx and Vy is the absolute ceiling. Can I call the peak of the coffin corner an absolute ceiling as well?
lemonincider's user avatar
  • 7,567
4 votes
1 answer
2k views

How can you find the best altitude for range or speed?

How can you select best cruise altitude (altitude for best range velocity) and maximum speed altitude? The specific case is a turboprop aircraft of gross weight 8000 lb.
glassgeek's user avatar
2 votes
1 answer
548 views

How is altitude correlated with true airspeed?

I am trying to understand the BADA 3.0 dataset (specifically I am looking at Performance Summary Tables): E.g. What is not obvious to me is why those tables mention only single TAS for specific FL. ...
thedk's user avatar
  • 123