Questions tagged [cruise]
The section of flight between the after takeoff climb and landing approach.
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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 ...
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How can an altimetry system error during cruise (500 ft at 35000 ft high) cause an insufficient fuel situation?
So my boss gave me a question today as my daily quiz: Let's say an A321 is cruising on a 6-hour flight. It reaches FL350 30 minutes after take-off. After another 8 minutes there's a discrepancy ...
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When might a pilot hand-fly a jet at cruise altitudes, and is it difficult?
How difficult is it to hand-fly a jet at cruise altitudes? Other than autopilot failure and just doing it for the fun of it, when might you want to hand-fly at those altitudes?
I suspect the answer ...
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Why do airliners pitch up during cruise?
In my experience as a passenger, when the plane stands at the airport and you enter it, the aisle is pretty much horizontal. (Obviously, I've never flown on a DC-3). After takeoff we pitch sharply ...
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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....
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Why are heavy flaps better than just a bigger wing?
Flaps increase lift during landing and T/O. But when retracted, they do nothing. The space needed to stow the common fowler flaps can't be used for anything else - fuel or structure. Extended flaps ...
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How much leverage do commerial pilots have on cruise speed?
If you fly frequently there are chances you have seen some delays in departure where you end up waiting in the aircraft sometimes for multiple hours.
Almost every time that happened I remember the ...
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Why do pilots announce the cruising altitude of a flight?
At some early stage in the flight, why will commercial pilots announce the cruising altitude of the flight?
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Would an airliner climb higher late in the flight because of the consumed fuel (lighter airplane) to save more fuel?
Some people said airplanes would fly higher in the late period of each flight, because the fuel is consumed, and the airplane is lighter. Higher altitude and less dense air is enough to support the ...
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How do planes maintain constant speeds at cruise altitudes?
I'm a noob so pardon my ignorance. So my understanding is that as the plane gets lighter during the flight, its mass reduces therefore reducing the lift needed to maintain the altitude. At those ...
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Do airliners reduce their angle of attack to maintain lift = weight as fuel burns off during cruise?
For an aircraft to remain in level flight, it must generate lift force that is exactly equivalent to its weight. However, modern airliners lose a lot of weight when they are in cruise flight in the ...
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Does flying slower actually save fuel?
Following a discussion on travel.SE, I wonder: would flying more slowly actually save fuel?
I suppose that it would save fuel on a volume of fuel per flight hour basis, but the flight would end up ...
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Why are planes required to cruise at round flight levels only above 18000 ft of altitude?
AFAIK, planes flying at up to FL180 (18,000 ft pressure altitude) are allowed to fly at both round and semi-round altitudes (e.g. 15,000 ft or 15,500 ft). Planes flying above FL180 must fly at a round ...
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How do planes know what altitude they're cruising at?
I know that when planes enter the aerodome containing the airfield of destination, the ATIS will tell them an altimeter setting so the system knows how to calculate their altitude above their field; ...
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Why do missiles typically have cylindrical fuselage and not a fuselage that generates more lift?
For example, Tomahawk Cruise Missile, or Harpoon anti-ship missile. They fly straight and level for the most part of their flight regime. I think if they had a fuselage optimised for level flight then ...
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What is the wing angle of attack of a Boeing 737 in cruise?
I would like to know the angle of attack that a 737 flies at during cruise. I am specifically interested in the wing angle of attack (if you know the cruise nose-up attitude and the wing incidence ...
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Is there research suggesting that VFR cruise altitude rules improve safety?
In the United States, 14 CFR 91.159 prescribes cruising altitudes for level flight under VFR:
(a) When operating below 18,000 feet MSL and
(1) On a magnetic course of zero degrees ...
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What is a Cruise Captain?
I wonder what is a Cruise Captain, albeit I assume they are here to fly the cruise phase.
Differences in responsibility / authority with a Captain?
From training / certificate standpoint, what is ...
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Will control surfaces on a plane be less efficient at a higher altitude?
I may be wrong but I learned that control surfaces depends on the air flow to work properly, and that airliners have a higher cruise altitude because of the less dense atmosphere, improving the fuel ...
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How do pilots decide what their cruising altitude will be?
When filing a flight-plan for a long-haul high-altitude IFR flight, how do pilots select a specific cruising altitude? Typically in the range of 25,000 - 35,000 ft.
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Can cruise pilots/second officers go for years without doing a takeoff or landing?
I was looking at the description of this role i.e. someone who provides cruise flight relief flying. As conceivably, someone could be bonded for multiple years because of the type rating being covered ...
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Do pilots keep light in the cockpit during long night flights?
During long times of the cruise flight, is the internal light normally switched on or off inside the cockpit?
Knowing it is generally dark in the night would make a smartphone-based night time logger ...
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Based on this fuel flow chart, why isn't it more optimum to remain at an intermediate altitude rather than climbing?
I am having a bit of confusing as to why people say planes gets more efficient as they fly higher. Because on a typical long haul flight the Fuel Flow of the aircraft will obviously be much more that ...
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What throttle setting does an airliner use while cruising?
As a passenger, I have always felt like the engine are not kept at take-off thrust/full throttle a few (tens of) seconds after take-off, and so for obvious reasons as fuel efficiency, engine wear ...
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Can airplane performance be increased by cruising "on step"?
Old timers swear aircraft performance can be increased by getting an aircraft "on step" similar to how boats are operated.
They claimed a couple extra miles per hour (airspeed was in MPH then) were ...
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How is the Dash 8 Q400 so fast?
The Q400 has a cruise speed of 360kts, and on flightradar24 most Q400s that I looked at reached similar speeds during cruise. The ATR 72 has similar specifications yet only flies at 280kts. I'm ...
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How to most likely get a flight that will go above 40,000 ft?
I wonder if there are passenger flights that would reach cruise altitudes higher than 40,000 ft (i.e. reach 41,000 ft for instance) more likely than others. It also depends on the plane of course, but ...
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Why is it that when autopilot is maintaining cruise, we don’t feel the changes when lift increases?
When we’re inside an aeroplane, when we’re in cruise, why is it that we don’t feel the changes in altitude, lift and the adjustments for example from the elevator on the plane as the weight is burned ...
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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? ...
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What happens if full thrust is applied at cruise altitude for 5-10 minutes on a 787?
What happens when you apply full throttle to the engines of a Boeing 787 at cruise altitude for 5-10 minutes?
Other than wasting fuel, what maximum speeds are reached?
Does that pose any danger or ...
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What is the throttle setting of a piston aircraft during cruise?
I am learning to fly nowadays, I am sorry if this sounds like a dump question.
What is the throttle setting of an aircraft during cruise flight?
After stabilizing the flight after climb do i need to ...
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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.
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Cruise Mach Number less or more than Critical Mach Number
Do commercial airplanes cruise at Mach number higher than the critical Mach number? And what is the critical Mach number of airplanes like B777 or A330?
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Why do B787 Dreamliners more often fly at 42,975 ft rather than at 43,000, according to flightradar24?
The A350 and the B787 are the only passenger airliners that can be seen cruising as high as 43,000 ft on flightradar24 (with the exception of a B747 I once saw). However, the B787 is more often found ...
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What would happen if thrust reversal is accidentally deployed during a flight? [duplicate]
Is it possible to deploy the thrust reversal, in the cruise phase of a flight? And, if they are accidentally deployed, what could be the possible consequences?
As the cruise phase requires a lot of ...
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How much does a Boeing 737 wing bend/deflect in cruise conditions?
As a part of my ongoing research of a structural joint analysis of a Boeing 737, I have been looking for sources where I may be able to find the bending/deflection data during cruise conditions. I ...
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How long after takeoff for a Boeing 747-400 to reach cruise speed?
Assume it is fully loaded (pasengers and cargo) and optimal conditions, almost no wind, etc etc...
How long after takeoff does the plane reaches cruise speed?
If he goes in a straight like on the ...
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Optimizing the airplane for best cruising altitude and velocity
In the conceptual phase of the design, I am optimizing various entities of an airplane for the best cruising altitude and speed to reduce the cost, which also includes MTOW and fuel weight. Consider a ...
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Does the Enroute Phase begin at a 30NM distance from the departure airport?
ICAO's Doc 8168 Volume II ("Aircraft Operations") states:
Part III "Performance-Based Navigation Procedures"
Section 1 "Underlying Principles"
Chapter 1 "RNAV ...
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Will a heavier aircraft be more efficient at high speeds(cruise)? [closed]
Since heavier aircraft have more mass and inertia, they will have less drag because it will be easier for them to push through the air so does that mean that we can achieve the same cruise speed with ...
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What is the Fuel-Oxygen ratio for a large turbofan at cruise conditions?
What is the Fuel-Oxygen ratio (by mass) for a large turbofan at cruise conditions?
In order to be concrete, I'll just pick an engine at random. I pick the GE90-115B. Okay it's not really random, it'...
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What is the main reason why cruise flight in the transition layer is prohibited?
What is the main reason why cruise flight in the transition layer is prohibited? For example if we have a separation of 1000 ft between transition altitude and transition level, why should we not ...
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Is there any existing engine which can be converted to turbofan from turboshaft in mid flight?
I read about convertible engines. I want to know if there is any engine existing to meet up hover and cruise together.
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Learn in-depth about airplane operations [closed]
Currently seeking a book or manual that teaches a civilian how a cargo aircraft operates and what it's pilots do, say a 787. Preferably a high-level overview at a per flight phase:
Pre-flight: Flight ...
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Why is the thrust-specific fuel consumption much worse for high bypass turbofans at cruise?
General Electric GE90
Takeoff: 0.278 lb/lbf/h (28.3 kg/kN/h)
Cruise: 0.545 lb/lbf/h (55.6 kg/kN/h)
Source: https://en.wikipedia.org/wiki/General_Electric_GE90#Specifications
I assume this is typical ...
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Relationship between wing aspect ratio and speed [duplicate]
For some reason, I cannot find a relatively straightforward source online which discusses the relationship of wing aspect ratio and how it affects speeds of an aircraft.
Specifically, is there a ...
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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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How does change in airspeed affect pitching moment?
In aircraft with conventional elevator control, if I increase the speed, the horizontal tail sees higher velocity and hence higher lift. Does it mean that increasing airspeed creates nose down ...
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How does drag change efficient cruise conditions?
If I have an aircraft, and I reduce the induced drag produced by it, does this mean I should operate it at a higher altitude and faster speed to take advantage of the drop in total drag, or slower at ...
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What are the effects of headwind on ground speed and take off run? [closed]
I'm just making sure I got this right.
For the take-off roll, having headwind is preferable, so there is a positive airspeed.
For the en-route segment, a headwind is not ideal and increases time to ...
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