Single engine climb at V2 or Vref ?
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i have read this thread and thanks to Mutt, Formulaben and moreso Darius for asking that question.Being a young and inexperienced pilot, i learn from people who ask questions n those who answer them genuinely. Experience is nothing here if all you do is rant about others.
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V2 instead of Vxse which could be Im guessing here V2+10 ?
The next question is when am i going to use that VSE speed? Any ideas Dariuszw? What did they teach you for the CJ?
Mutt
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Mutt - Difference between my V2 and Vt is 23kts so V2 and Vxse could not be nearly as much as your bus 
. How much I would like to know myself since I cant find Vxse anywhere.
Now, to answer your patronizing question:
My idea of speed use in case of SE was until recently this: rotate, fly V2 (which I thought to be my Vxse.....NOT!), at 1500' fly Venr (Vyse).
Now, Mutt its your turn to shine and explain why I should fly V2 - like Cessna recommends - instead of Vxse till 1500ft. I would rather use best angle of climb till 1500ft for obsticle clearance rather then minimum flying speed. So what say you ....
formulaben - Not so fast, If you read my posts carefully you would see I that I said Vref accelerates above V2 way before I reach flap retraction height of 1500ft. Five seconds later Vref was about 10kts above V2 and flaps have not yet moved an inch.Thats why I believe speed acceleration had something to do here. Look at this picture here...
. How much I would like to know myself since I cant find Vxse anywhere.Now, to answer your patronizing question:
My idea of speed use in case of SE was until recently this: rotate, fly V2 (which I thought to be my Vxse.....NOT!), at 1500' fly Venr (Vyse).
Now, Mutt its your turn to shine and explain why I should fly V2 - like Cessna recommends - instead of Vxse till 1500ft. I would rather use best angle of climb till 1500ft for obsticle clearance rather then minimum flying speed. So what say you ....
formulaben - Not so fast, If you read my posts carefully you would see I that I said Vref accelerates above V2 way before I reach flap retraction height of 1500ft. Five seconds later Vref was about 10kts above V2 and flaps have not yet moved an inch.Thats why I believe speed acceleration had something to do here. Look at this picture here...
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I would rather use best angle of climb till 1500ft for obsticle clearance
But for those operators who do analyze obstacles, they will discover that the air-distance required to accelerate will mean that they cannot clear the close-in obstacles, so that's why people keep advising you to use V2/V2+10.
Mutt
Dariuszw, V2 isn't necessarily a best angle of climb speed. It's a scheduled speed that, if followed, will enable the aircraft to meet the performance shown in the performance charts. Those charts account for the various regulatory requirements, including obstacle clearance at various distances from the take-off point.
Accelerating from V2 to Vx doesn't happen instantly. Nor is it 'free' ie there is a performance penalty during the acceleration phase. In this case, angle of climb. During that *short term* reduction in climb angle the aircraft may no longer meet the net climb gradient that obstacles or the rules require. You are correct in the sense that Vx will provide better climb angle than V2, however *getting* to Vx initially results in performance that may not meet the requirements.
There is a case where increasing speed can improve performance. Or, more usually, allow a greater take-off weight: Using an 'increased V2' or 'improved climb' or similar language. This is used to get a better climb angle to clear an obstacle further along the take-off path at the expense of using more runway & provided there aren't any limiting close in obstacles.
Accelerating from V2 to Vx doesn't happen instantly. Nor is it 'free' ie there is a performance penalty during the acceleration phase. In this case, angle of climb. During that *short term* reduction in climb angle the aircraft may no longer meet the net climb gradient that obstacles or the rules require. You are correct in the sense that Vx will provide better climb angle than V2, however *getting* to Vx initially results in performance that may not meet the requirements.
There is a case where increasing speed can improve performance. Or, more usually, allow a greater take-off weight: Using an 'increased V2' or 'improved climb' or similar language. This is used to get a better climb angle to clear an obstacle further along the take-off path at the expense of using more runway & provided there aren't any limiting close in obstacles.
