Single engine climb at V2 or Vref ?
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Single engine climb at V2 or Vref ?
Has any one of you noticed this phenomena that when taking off soon after rotation Vref becomes higher then V2. That's the case at least in Citation. Its a bit problematic since in case of single engine climb below 1500ft V2 is expected to be mainteined. I do not think Cessna expects me to fly below Vref ..... I would in such case increase the speed to Vref and fly that instead of V2. Any idea why Vref increases so quick ???
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Your a 17 year old citation pilot and one of your interests is flight sims?
And this gem from a previous post
There is nothing wrong with asking questions but pretending to be a citation pilot is a bit weird.
And this gem from a previous post
Question:
I understand we reduce thrust due to warmer then standard temps or higher then standard density altitude in order to limit I guess ITT and preserve this way engine life. But N1 is reduced also when temp are colder then standard. Is it because of stractural limits or what.... ??
I understand we reduce thrust due to warmer then standard temps or higher then standard density altitude in order to limit I guess ITT and preserve this way engine life. But N1 is reduced also when temp are colder then standard. Is it because of stractural limits or what.... ??
Ah, Vref=Reference LANDING speed, V2=TAKEOFF safety speed.
The technical answer is V2 protects you to a 30 degree bank, Vref protects you to 40. Yes, Cessna in this case expects you to fly your CLIMBOUT at a lower speed that you would fly your APPROACH. Cessna would not expect you to maneuver as radically on takeoff as on landing.
The technical answer is V2 protects you to a 30 degree bank, Vref protects you to 40. Yes, Cessna in this case expects you to fly your CLIMBOUT at a lower speed that you would fly your APPROACH. Cessna would not expect you to maneuver as radically on takeoff as on landing.
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Disagree, Vref has nothing to do with approach speed during climb out as it simply represents 1.3 of stall speed and is represented by green donut during takeoffs and landing. I'm sure Cessna does not want me to fly below 1.3 stall speed... right ? No jet should be flown below 1.3 stall speed. I cant believe there is not even one person who noticed that as well and can explain it. So perhaps someone can just tell me why Vref increases so quickly and please avoid ground effect explenation as the increase starts well above ground effect alitutde.
Sloppy - when you will have half of my knowledge at 40 then perhaps you'll get to fly sport car as well and for now go back to your 737 bus and fly your freight
Sloppy - when you will have half of my knowledge at 40 then perhaps you'll get to fly sport car as well and for now go back to your 737 bus and fly your freight
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Gents, Dariuszw is a Walter Mitty who started off under the user name SSG, and has had about a dozen incarnations since. Claims to fly a Citation Ultra and has a disposition to flail anyone with real experience, such as mutt or Galaxy Flyer. Favourite subject is advocating rejecting after V1.
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No jet should be flown below 1.3 stall speed
I presume that you do know what Vs1G is?
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Mutt, perhaps that's true, I have not flown in my SIM 
other jets then CJ so my statement is perhaps too broad. Nonetheless Citation is providing me with a green donut throughout my flight envelop on my Collins Proline PFD which it claims to be Vref of 1.3 Vs. So let me correct my statement: " No jet should be flying below Vref...right ? " Now, has anyone noticed what I have noticed ? Am I correct to assume Vref as minimum speed instead of V2 in such situation ? and does anyone have a clue as to why Vref increases so quickly above V2 ???
other jets then CJ so my statement is perhaps too broad. Nonetheless Citation is providing me with a green donut throughout my flight envelop on my Collins Proline PFD which it claims to be Vref of 1.3 Vs. So let me correct my statement: " No jet should be flying below Vref...right ? " Now, has anyone noticed what I have noticed ? Am I correct to assume Vref as minimum speed instead of V2 in such situation ? and does anyone have a clue as to why Vref increases so quickly above V2 ???
SSG I think I know who you had at CAE for the Citation course Ms. Tooey -Currently Mrs. Hollaway-' Cuz you sure do talk a whole lotta hooey, but I must admit you're a riot, a real riot....
skip to 18:00 -a classic episode indeed
I know.
Darius,
If V2 was your safety speed at rotation, how is it you you thnk it suddenly becomes unsafe once you are airborne?
Try reading up the definitions of those speeds- that might help....
If V2 was your safety speed at rotation, how is it you you thnk it suddenly becomes unsafe once you are airborne?
Try reading up the definitions of those speeds- that might help....
Vref is final approach speed, V2 takeoof safety speed....Apples and Oranges--- different max weights different certification criteria different phases of flight....
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However, Vref and V2 are VERY close at a given weight (at least in the 747), so V2 can successfully be used in place of Vref in the case of an immediate emergency return for landing, if there's no time to get into the books.
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In the L1011, VREF was used on takeoff as a Fuel Dumping limitation with Flaps 04, so as others have stated, they are extremely similar but based on different certification criteria.
(I miss 411A whenever i mention the L1011
)
(I miss 411A whenever i mention the L1011
)
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Im quite surprised that none of you know what Im talking about. Perhaps due to different avionic systems. But then let me ask you this: how do you know whats your 1.3 or 1.23 vs so called Vref during cruise ? After all you have not yet set up landing speeds yet. In CJ Vref is represented by green donut computed by computer and displayed entire time from start to land. V2 is taken from charts and is fixed. And when during takeoff Vref rises above V2 I assume Vref as minimum speed to fly and no longer V2. I think this might be CJ thing only so will adress this somewhere else. Ether way thank you for your answers !
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Are you talking about all engine takeoff or engine failure on takeoff? If engine failure, then surely the concept is to fly V2-V2+10 until flap retraction altitude then accelerate to VFS followed by VSE?
We have the Vref for the present configuration available to us at all times, but as we have stated to you, it doesnt figure in our takeoff mentality.
We have the Vref for the present configuration available to us at all times, but as we have stated to you, it doesnt figure in our takeoff mentality.