Single engine climb at V2 or Vref ?
Airbii have "green dot" speed in the PFD, also
Mutt
Funny thing, one didn't need to mention the L-1011 TrStar to have 411A bring the thread around to the L1011. Haven't checked, but I'll bet he could get the L10 into a thread about Pitts Specials.
Mutt
Funny thing, one didn't need to mention the L-1011 TrStar to have 411A bring the thread around to the L1011. Haven't checked, but I'll bet he could get the L10 into a thread about Pitts Specials.
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Im quite surprised that none of you know what Im talking about.
On takeoff and initial climb, we use V2 and don't explicitly worry about Vref. The exception is an immediate return; and as I explained earlier, V2 is a reasonable replacement for Vref in that case. In cruise, we don't worry about either one. On descent, approach, and landing we worry about Vref and not V2. While we "know" in the back of our minds what kind of protections we are given by each number, we don't worry about the specifics real-time.
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V2 is not a fixed speed it varies with weight, between take off and landing you will burn a significant amount of fuel (weight) so vref will be determined by landing weight. V2 is not a factor during landing as previously stated. Cruise speed is typically a mach number (unless flying at a low altitude) based on weight and altitude and temperature and is not a fixed number. High speed/low speed buffet limits and g protection come into play here. I think you are trying to simplify something which is not always so simple.
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No, it happens below 1500' as we continue takeoff with simulated engine out well above ground effect and after gear up. So no configuration changes take place at that time. Cessna advises to climb at V2 which is set on the ground based on field elevation and weight but does not take into consideration increasing altitude during climb out. It cought me by surprise as to how quicly Vref climbs over V2 and Im not sure as to why but Im quite convinced I should not fly below Vref as its constantly recomputed and adjusted by FMS.
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V2 is 1.13 times Vs1G (1.2 Vs) while VREF is 1.23 times Vs1G (1.3 Vs), so as you are talking about the same configuration on takeoff, would you not expect the Vref to be higher?
Your error is that you now think you should fly this higher speed, but have you considered that if you continue to chase the Vref speed, what is going to happen to your climb gradient? What happens to your 35 feet clearance over the obstacles?
Your error is that you now think you should fly this higher speed, but have you considered that if you continue to chase the Vref speed, what is going to happen to your climb gradient? What happens to your 35 feet clearance over the obstacles?
It´s such a silly question that I wouldn't have even thought it worth answering yet we have two pages on it.....crazy. It is like asking ¨How come the manufacturer of my car suggests using th foot pedal brakes while driving yet suggests using the park brake when stopped on a hill?....surely they don't want me to not use the foot pedal?¨ It just shows a complete lack of understanding of driving a car.
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Well ladies, I really would hate to waste your time and as some of you already know me, Im a gambling person. So here is your big chance to prove yourself. Care to put some money that what Im stateting is pure nonesense ???? Im in EDDL right ´now and have two more flights tonight on my .....SIM yet so when I get back home tonight I will accept any of your bets and then I will post pictures from my last flight proving it true. Till then...
Lets see if de Facto will be the first here to bet with this foolish 17 year old Darius ;-)
Lets see if de Facto will be the first here to bet with this foolish 17 year old Darius ;-)
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Well if your are telling the truth well done on having a total lack of understanding and putting your passengers at risk. Surely you should know this before you get in the plane. Chasing an increasing speed with an engine failing at V1, you truly are an incompetent fool.
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Darius,
What we are saying to you is:
We know what you are observing is correct, that your V2 is lower than your Vref.
V2 and Vref aren't the same, don't treat them the same....
What we are saying to you is:
We know what you are observing is correct, that your V2 is lower than your Vref.
V2 and Vref aren't the same, don't treat them the same....
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Im not sure as to why but Im quite convinced I should not fly below Vref
I suggest before this mentality kills you and your pax that you follow your sops/aircraft training manual.
Is that true your pax pay big money to be flown by you?
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Since I will not address each and everyone of those you know what....Let this be a lesson to all the rest of you ! There are many who will spew nonesense all day long here insulting others but when told to put weight behind what they spew none will have the guts ! So if u cant put money where your mouth is then you are just static, irrelevent, wasted time ! Mutt - You are absolutely correct. V2 is 1.2Vs and as such should be in theory less then Vref. My incorrect thinking was that I always assumed V2 to be equivalent to Vxse ( best angle of climb with single engine) which should be at or above Vref and that is not correct. V2 is minimum flying speed and is less then Vxse. That would explain Vref climb above V2 but why then it starts about 10kts below V2 hmm... ?
Mutt to aswer your question -what would happen to my climb performance and gradient if I increase my speed above V2 (up to some point) - I would answer that my climb performance and gradient will increase since V2 is not a performance limiting speed (like Vxse or Vyse)but mere minimum allowed flying speed with single engine. Do you disagree ?
Feel free guys to explain how your logic fits to this picture....be my guest !
Last edited by Dariuszw; 1st Mar 2012 at 13:22.
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Quite simple: your V2 bug is a fixed bug, meaning it is calculated and then fixed to the airspeed tape. Your Vref bug is AoA CALCULATED...if in anything other than stabilized flight (accelerated flight) and IT WILL MOVE. Also, those bugs are usually FLAP COMPENSATED...I see you are 270 feet off the ground. Did you do a flaps 0 takeoff?
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There are many who will spew nonesense all day long here insulting others but when told to put weight behind what they spew none will have the guts ! So if u cant put money where your mouth is then you are just static, irrelevent, wasted time
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formulaben - It was 15 degrees of flaps t/o all the way to 1500ft but perhaps your explenation could be correct as FMS might have a delay due to continued acceleration which can be seen by trend indicator. This film has been taken by colique of mine for maintenance consultation and comparison to other aircrafts in our fleet. I like your explenation and I think you might be right on the money 
Thank you !
One more thing that is a bit confusing for me is: V2.
Since V2 according to what I read is not Vxse but rather minimum flying speed with single engine then what is Vxse and why Cessna adiveses to maintain V2 instead of Vxse which could be Im guessing here V2+10 ?
Thank you !One more thing that is a bit confusing for me is: V2.
Since V2 according to what I read is not Vxse but rather minimum flying speed with single engine then what is Vxse and why Cessna adiveses to maintain V2 instead of Vxse which could be Im guessing here V2+10 ?
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It was 15 degrees of flaps t/o all the way to 1500ft but perhaps your explenation could be correct as FMS might have a delay due to continued acceleration which can be seen by trend indicator.