Some general questions! Help please!
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Some general questions! Help please!
Hy guys, I'm preparing my assessment for an airlinner and I need some help to answer a few questions. Would you mind helping me collegues?
Thanks in advance!
*Why fuel-injected engines, what would happen if your primer kept operating while climbing with a SEP, temp range carb icing?
*What is the maximum operating ceiling of a typical jet?
*Why will a jet not fly this altitude?
*When will a jet be able to fly this altitude?
*Why do jet a/c fly as high as possible?
*If turboprops are more efficient a/c why do they not climb that high?
*What would you do if you had a radio failure on take off?
*You are on a flight from Stansted to Amsterdam and just after T/O are at your cleared level of 2000ft when you have complete radio failure. What are your actions?
*Which is faster, London to New York or New York to London? Why?
Thanks in advance!
*Why fuel-injected engines, what would happen if your primer kept operating while climbing with a SEP, temp range carb icing?
*What is the maximum operating ceiling of a typical jet?
*Why will a jet not fly this altitude?
*When will a jet be able to fly this altitude?
*Why do jet a/c fly as high as possible?
*If turboprops are more efficient a/c why do they not climb that high?
*What would you do if you had a radio failure on take off?
*You are on a flight from Stansted to Amsterdam and just after T/O are at your cleared level of 2000ft when you have complete radio failure. What are your actions?
*Which is faster, London to New York or New York to London? Why?
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*What is the maximum operating ceiling of a typical jet? -40,000 feet or so, if we are talking about commercial transport types *Why will a jet not fly this altitude? -Pressurisation is usually the main issue- the difference in pressure is too high for the aircraft body to cope with *When will a jet be able to fly this altitude? -If and when the cost of stronger body is less than the extra fuel needed to carry it around *Why do jet a/c fly as high as possible? -Thinner air, less air resistance (in simple terms) *If turboprops are more efficient a/c why do they not climb that high? -Not sure to be honest *What would you do if you had a radio failure on take off? -There are almost always specific or generic radio failure procedures, see bellow *You are on a flight from Stansted to Amsterdam and just after T/O are at your cleared level of 2000ft when you have complete radio failure. What are your actions? -http://www.nats-uk.ead-it.com/aip/current/enr/EG_ENR_1_1_en.pdf Section 4.2.2 and 4.2.4 *Which is faster, London to New York or New York to London? Why? -New York to London (usually) as the jetstream across the Atlantic is in that direction- hence a greater groundspeed for most of the trip toward Europe. EDIT: No idea why, but all the formatting has disappeared, and I can't be bothered fixing it.
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*What is the maximum operating ceiling of a typical jet?
*Why will a jet not fly this altitude?
*When will a jet be able to fly this altitude?
*Why will a jet not fly this altitude?
*When will a jet be able to fly this altitude?
However, I think that you should Google "Coffin Corner", "Stall speed versus altitude" and "Maneuver capability at altitude".
Have a look around and then let us know what YOU think.
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*Why fuel-injected engines, what would happen if your primer kept operating while climbing with a SEP, temp range carb icing?
Reduced susceptibility to carb icing and the effects of g, better and more even fuel distribution, smaller parts count. A stuck primer may flood the engine. Between 0 and 15 degrees Celcius OAT is the worst range, but some charts show the possibility of icing occurring between -15 to +35.
*What is the maximum operating ceiling of a typical jet?
Late 30's, early 40's due: Fuselage strength/weight (due pressurisation), lack of power to poke to there and once you are there, insufficient stall and buffet margins. However, once you get there, flying can be easier because there are not so many aircraft up there, thus better routings can made.
*Why will a jet not fly this altitude?
See above. Or if it can get there sometimes, but not today it could be due to current weight or SAT limitations (for poor Embraer drivers).
*When will a jet be able to fly this altitude?
See one and two above.
*Why do jet a/c fly as high as possible?
Possibility of optimal fuel consumption and preferential routings together with higher TAS.
*If turboprops are more efficient a/c why do they not climb that high?
To be efficient at altitude, you have to fight the effects of compressibility. This means thinner, swept wings, more sophisticated propellers and heavier airframes to deal with higher cabin differentials. This would remove some of the operating advantages of turboprops. Additionally, at FL250 and below you don't have to have drop-down O2.
*What would you do if you had a radio failure on take off?
As Diaz pointed out - standard radio failure unless local and national procedures indicate otherwise. But carrying on with what you were cleared to do and squawking 7600 would be a good start.
*You are on a flight from Stansted to Amsterdam and just after T/O are at your cleared level of 2000ft when you have complete radio failure. What are your actions?
As above.
*Which is faster, London to New York or New York to London? Why?
See Diaz's post.
PM
Reduced susceptibility to carb icing and the effects of g, better and more even fuel distribution, smaller parts count. A stuck primer may flood the engine. Between 0 and 15 degrees Celcius OAT is the worst range, but some charts show the possibility of icing occurring between -15 to +35.
*What is the maximum operating ceiling of a typical jet?
Late 30's, early 40's due: Fuselage strength/weight (due pressurisation), lack of power to poke to there and once you are there, insufficient stall and buffet margins. However, once you get there, flying can be easier because there are not so many aircraft up there, thus better routings can made.
*Why will a jet not fly this altitude?
See above. Or if it can get there sometimes, but not today it could be due to current weight or SAT limitations (for poor Embraer drivers).
*When will a jet be able to fly this altitude?
See one and two above.
*Why do jet a/c fly as high as possible?
Possibility of optimal fuel consumption and preferential routings together with higher TAS.
*If turboprops are more efficient a/c why do they not climb that high?
To be efficient at altitude, you have to fight the effects of compressibility. This means thinner, swept wings, more sophisticated propellers and heavier airframes to deal with higher cabin differentials. This would remove some of the operating advantages of turboprops. Additionally, at FL250 and below you don't have to have drop-down O2.
*What would you do if you had a radio failure on take off?
As Diaz pointed out - standard radio failure unless local and national procedures indicate otherwise. But carrying on with what you were cleared to do and squawking 7600 would be a good start.
*You are on a flight from Stansted to Amsterdam and just after T/O are at your cleared level of 2000ft when you have complete radio failure. What are your actions?
As above.
*Which is faster, London to New York or New York to London? Why?
See Diaz's post.
PM
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*Why will a jet not fly this altitude?
*What would you do if you had a radio failure on take off?
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Thanks again guys! Now I have a little problem with three different concepts:
*maximum service ceiling.
*absolute ceiling.
*maximum operating ceiling.
If I m not confused, the first also means an aircraft's density altitude at which its maximum rate of climb is lower or equal to 100 feet per minute.
The absolute celing is the highest altitude at which the aircraft can maintain level flight.
The second one, The absolute celing is the highest altitude at which the aircraft can maintain level flight.
And de maximum operating ceiling is about the problems with pressurisation (the body aircraft can't cope with it)
But if we talk about the Mcrit, Coffin Corner and Speed stall, What is the ceiling limitation? Are we talk about the absolute ceiling too? Sorry but this the point where I get confused!!!
*maximum service ceiling.
*absolute ceiling.
*maximum operating ceiling.
If I m not confused, the first also means an aircraft's density altitude at which its maximum rate of climb is lower or equal to 100 feet per minute.
The absolute celing is the highest altitude at which the aircraft can maintain level flight.
The second one, The absolute celing is the highest altitude at which the aircraft can maintain level flight.
And de maximum operating ceiling is about the problems with pressurisation (the body aircraft can't cope with it)
But if we talk about the Mcrit, Coffin Corner and Speed stall, What is the ceiling limitation? Are we talk about the absolute ceiling too? Sorry but this the point where I get confused!!!
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ceilings
hello agus,
keep it simple : any powered aircraft has amongst other things : wings(2) & engine(s), so you have a max. altitude for the wings(aerodynamic ceiling) & a max. altitude for the engine(s)[propulsive ceiling]. which one you reach first depends on the choices(compromises) of the aircraft manufacturer. in general & of course i oversimplify, american planes are "overpowered", so you will reach the aerodynamic ceiling first, whilst european built aeroplanes are sometimes "underpowered" & reach the propulsive ceiling first.
now lets elaborate a little further : "altitude" in this context, means "density" altitude or "pressure" altitude(1013hPa), corrected for temperature.
aerodynamic max.altitude(max.ceiling) is that altitude where low speed stall & high speed stall(due to shockwaves), are the same. it is the so called "coffin corner".
the propulsive max.altitude, is that altitude, where max thrust from the engine(s) equals the drag. there is only one speed to fly for this : Vmin drag=finesse max =Cl/Cdmax.
absolute ceiling, is ceiling where rate of climb=0.
service ceiling(lower than absolute), is ceiling where you still have a small rate of climb available. lets finish with an example.
for the 738 max altitude/fl is the lowest of :
1) 41000ft, is a certified structural limit(max delta pressure).
2) max. cruise altitude(fms).
depends on the thrust/drag relationship
needs a min rate of climb of 150ft/min
is temperature dependent
3) buffet limits : not lower than 1.3g in smooth air.
greetings,
bm.
keep it simple : any powered aircraft has amongst other things : wings(2) & engine(s), so you have a max. altitude for the wings(aerodynamic ceiling) & a max. altitude for the engine(s)[propulsive ceiling]. which one you reach first depends on the choices(compromises) of the aircraft manufacturer. in general & of course i oversimplify, american planes are "overpowered", so you will reach the aerodynamic ceiling first, whilst european built aeroplanes are sometimes "underpowered" & reach the propulsive ceiling first.
now lets elaborate a little further : "altitude" in this context, means "density" altitude or "pressure" altitude(1013hPa), corrected for temperature.
aerodynamic max.altitude(max.ceiling) is that altitude where low speed stall & high speed stall(due to shockwaves), are the same. it is the so called "coffin corner".
the propulsive max.altitude, is that altitude, where max thrust from the engine(s) equals the drag. there is only one speed to fly for this : Vmin drag=finesse max =Cl/Cdmax.
absolute ceiling, is ceiling where rate of climb=0.
service ceiling(lower than absolute), is ceiling where you still have a small rate of climb available. lets finish with an example.
for the 738 max altitude/fl is the lowest of :
1) 41000ft, is a certified structural limit(max delta pressure).
2) max. cruise altitude(fms).
depends on the thrust/drag relationship
needs a min rate of climb of 150ft/min
is temperature dependent
3) buffet limits : not lower than 1.3g in smooth air.
greetings,
bm.
