CWHS

引用:

原帖由 odyssey2007 於 25-7-2010 15:55 發表


講緊thrust vectoring 又講aileron??
你知唔知f22 點樣唔郁control surfaces 單靠thrust vectoring 黎roll 先? 一邊engine out 單靠thrust vectoring 你點roll???
又講下aileron, 主翼面瀕臨stall 既情況突然一 ...

只係用aileron做例子, 一邊INOP, 另一面function到就Roll唔到嗎?
我相信你明白好多戰機即使到Stall Speed甚至Negative Speed Control Surface依然能夠控制A/C吧
而F-22當年贏YF-23的原因?

此example 以F-22解決方法, Roll Left and sightly pitch down + Apply Full Thrust + Apply Left Rudder -> Control Surface + Thrust Vectoring help Roll Left + rudder compensate -> Recovery.

CF-18見到的是Tailspin stall, 係F-18上係有Spin Recovery System, 會指示recovery, pilot亦要maintain指定AOA.

additional 只要maintain個yaw, 就算both eng flameout, 都唔止得個4秒Lift

[ 本帖最後由 CWHS 於 25-7-2010 16:24 編輯 ]

odyssey2007

睇黎你真係唔知f22 點樣唔郁control surfaces, 單靠thrusting 黎roll 呢...

yup, with both engine running+ thrust vectoring+ 自身某o的氣動特性, then? apply 落今次既situation, 有幫助?
我一直都講緊係唔夠高度亦唔夠時間, o個o的機既control surface 係control 到, 但係好靈敏? 有冇留意o個o的機做呢o的所謂過失速機動時要幾多空間? 要幾多thrust?

咁既高度有幾多room 俾你pitch down? 有幾多時間俾你跟instruction 黎做?

由頭到尾我都講緊得番一個engine + 高aoa+ 低速度+ 低高度 時既flight envelope, 你就係咁同我講normal 時既flight envelope...

飛到上去就唔係淨係睇架機數字上既性能ga la...要睇埋當時既飛行條件, o係咩空域, etc.

CWHS

Double post Del....

[ 本帖最後由 CWHS 於 25-7-2010 17:02 編輯 ]

CWHS

Triple Post del..

[ 本帖最後由 CWHS 於 25-7-2010 17:02 編輯 ]

CWHS

引用:

原帖由 odyssey2007 於 25-7-2010 16:36 發表
睇黎你真係唔知f22 點樣唔郁control surfaces, 單靠thrusting 黎roll 呢...

yup, with both engine running+ thrust vectoring+ 自身某o的氣動特性, then? apply 落今次既situation, 有幫助?
我一直都講緊係唔夠 ...

師兄, 你會唔會又頭到尾都係到誤解我, 我無話F-22的Roll是靠Thrust Vectoring Thrust Vectoring只是 Assistance.
CF-18的情況是4秒後Tailspin, If maintain Yaw, A/C Lift會唔止4秒(Perhaps +2~+4), 而Jet ENG Respond要唔要6~8秒?
計算AOA+Low Speed帶多的penalties落埋去, 小弟目視估計當時at least 500ft+, 而認為係呢個envelope下, 對F119有幾大的影響?
要做的只要係失去Lift前令A/C增加Lift就可以Recovery, Civ Twin ENG Jet有好多單都係single Eng flamout + High AOA at final approach, 但又救得番, 反而Mil Jet就唔得?

btw 個Fly by要飛行條件話觀眾安全姐, 但做咩要理Airspace class

CWHS

引用:

原帖由 odyssey2007 於 25-7-2010 16:36 發表
睇黎你真係唔知f22 點樣唔郁control surfaces, 單靠thrusting 黎roll 呢...

yup, with both engine running+ thrust vectoring+ 自身某o的氣動特性, then? apply 落今次既situation, 有幫助?
我一直都講緊係唔夠 ...

btw師兄, pm個MSN黎啦 同你傾空有排傾

odyssey2007

都話睇番個situation, 得番單邊engine 既話以f22 既thrust vectoring 頂多做到少少pitching, 有咩用?
engine 就算o係咁既環境o係4 秒裡面俾到respon 你, 唔好唔記得你只係得一個engine, 仲要唔知上唔上得切high power, 架機o係咁既aoa 勁大drag, 要改變架機既慣性既方向唔係做唔到, 而係會慢(因為俾唔夠energy), 所以我話救唔切

flight envelope 唔係咁解...

你以為500ft 好多? 就算架機得100kts 500ft 真係透啖氣就冇左

失去lift 之前加埋lift, 講就易, 一架原本design 由兩個engine 推既飛機你要佢o係咁高aoa 用一個engine 好快咁加速黎gain lift?? 唔夠power 就要用時間黎speedup 黎gain lift, e 家問題係唔夠時間

civil twin eng 一邊flame out 做approach 根本唔駛救, 因為佢有高度同原本已經有既速度(如果兩樣都冇既話都唔駛救, 嘥氣), 唔夠速度就用高度黎換速度
你話civil twin aoa 大? 冇錯, 佢地landing 可以差唔多20 度aoa 都得, 一o的問題都冇, 知唔知咩係multi slot flap?

唔明我講乜?
你有冇留恴o的特技飛行o係開始既時候係o係咩高度? 個動作完o個時o係咩高度? 高度差有幾多?
如果你e 家o係500ft, 但係做某個動作會損失800ft 高度, 你仲會唔會做?

CWHS

引用:

原帖由 odyssey2007 於 25-7-2010 17:36 發表
都話睇番個situation, 得番單邊engine 既話以f22 既thrust vectoring 頂多做到少少pitching, 有咩用?
engine 就算o係咁既環境o係4 秒裡面俾到respon 你, 唔好唔記得你只係得一個engine, 仲要唔知上唔上得切high pow ...

師兄呀師兄
MFD+HUD(If function select)+VOICE會出
"bleed air right" + "engine right", "Caution" + "Warning" button + Alarm.
讀個Civ PPL都會教你點做, 一個熟練的Pilot理應了解自己部機的Aerodynamic同flight control, 唔會做出Over Limitation 既事, 由求會致命, 可述係一個Combat Aviator, 唔會你Left Eng INOP敵人就唔打你架ma
而500ft係唔多, 但做到既野唔可以話小, 由求對一部aerodynamic instability咁好既機, 一日你部A/C有Airflow都仲可以郁.
小弟對師兄提出4-8秒內, Engine唔能夠時間respon好有疑問, 除非部機係Full Loading Weapon & Fuel, 否則反應唔會話stall左都未有thrust. 作為一部5th Gen Fighter, 唔會以係4-8秒內respon thrust, 同唔可以achive幾Kts?
經十幾分鐘search完又search, 得知F-15c任可情況下可以4秒內由idle到Full Thrust. 仲搵到句咁既樣, 但師兄應該又會話一邊INOP, 但好像我一直都提及INOP, 亦沒有忘記帶來的pepenalties...(F-22試過4500ft做yoyo maneuver落番唔低過2000ft, 當然both eng ok)
"The two-dimensional nozzle vectors thrust 20 degrees up and down for improved aircraft agility. This vectoring increases the roll rate of the aircraft by 50 percent and has features that contribute to the aircraft stealth requirements."

And 師兄我提出的Civ案例是指 Exceed而唔係Standard Operation AOA, 而唔係話佢地AOA大, 講AOA大, Military Cargo可以仲大. 竟然談到slotted flap呀
事發中CF-18又無事->Tailspin目視估計只係drop左no more than 100ft.
"In aerodynamics, the flight envelope or performance envelope of an aircraft refers to the capabilities of a design in terms of airspeed and load factor or altitude."
"計算AOA+Low Speed帶多的penalties落埋去, 小弟目視估計當時at least 500ft+"我句野又有事? ,講緊AOA + Low Speed Performance limitation.
車同飛機都有樣叫minimum turning radius既東西, 做特技時都excced左呢個limit, 造成好多的能量流失.........但...與直線Flyby無關係哦...

btw師兄有無學過stall/tailspin recovery呢...

odyssey2007

引用:

師兄呀師兄
MFD+HUD(If function select)+VOICE會出
"bleed air right" + "engine right", "Caution" + "Warning" button + Alarm.
讀個Civ PPL都會教你點做, 一個熟練的Pilot理應了解自己部機的Aerodynamic同flight control, 唔會做出Over Limitation 既事, 由求會致命, 可述係一個Combat Aviator, 唔會你Left Eng INOP敵人就唔打你架ma  亦都唔會因為有人打你你就可以restore 得快o的...
而500ft係唔多, 但做到既野唔可以話小, 由求對一部aerodynamic instability咁好既機, 一日你部A/C有Airflow都仲可以郁.

我成日都o係度講, 唔係唔郁得, 係你郁唔郁得切...電腦係會俾instruction 你...都話...問題係你做唔做得切...你follow 晒黎做要幾耐?你o係咩高度?學你咁講500ft既話你覺得你會夠時間做晒+ restore 到? 唔得先eject? 到時你既高度, 速度同姿勢又一定會適合你eject?

小弟對師兄提出4-8秒內, Engine唔能夠時間respon好有疑問, 除非部機係Full Loading Weapon & Fuel, 否則反應唔會話stall左都未有thrust. 作為一部5th Gen Fighter, 唔會以係4-8秒內respon thrust, 同唔可以achive幾Kts?
經十幾分鐘search完又search, 得知F-15c任可情況下可以4秒內由idle到Full Thrust. 仲搵到句咁既樣, 但師兄應該又會話一邊INOP, 但好像我一直都提及INOP, 亦沒有忘記帶來的pepenalties...(F-22試過4500ft做yoyo maneuver落番唔低過2000ft, 當然both eng ok)
"The two-dimensional nozzle vectors thrust 20 degrees up and down for improved aircraft agility. This vectoring increases the roll rate of the aircraft by 50 percent and has features that contribute to the aircraft stealth requirements."

氣流差到一邊engine surge/stall 既話另一邊engine 點會可以o係4 秒裡面推到full? 倒番轉諗, 一邊可以o係4 秒裡面推到full, 另一邊仲駛surge/stall??

咁我直接問...一架f22 o係45度aoa, stalling, 1 engine inop 既情況下要restore 要幾多時間, 損失幾多高度? 然後你計下500ft - 你得出黎要損失既高度, 係正數定負數? 正數既話正到幾多?

And 師兄我提出的Civ案例是指 Exceed而唔係Standard Operation AOA, 而唔係話佢地AOA大, 講AOA大, Military Cargo可以仲大. 竟然談到slotted flap呀

咁你個example 係幾多aoa, standard aoa of o個個stiuation 又係幾多?
至於slotted flap 同aoa of approch 有咩關係唔駛我講la

事發中CF-18又無事->Tailspin目視估計只係drop左no more than 100ft.
"In aerodynamics, the flight envelope or performance envelope of an aircraft refers to the capabilities of a design in terms of airspeed and load factor or altitude."
"計算AOA+Low Speed帶多的penalties落埋去, 小弟目視估計當時at least 500ft+"我句野又有事? ,講緊AOA + Low Speed Performance limitation.

你睇番你之前句野講乜?

車同飛機都有樣叫minimum turning radius既東西, 做特技時都excced左呢個limit, 造成好多的能量流失.........但...與直線Flyby無關係哦...

我係講not enough room for that maneuver

btw師兄有無學過stall/tailspin recovery呢...

我直都唔係話唔夠高度同時間救, 如果高度有番千幾二千ft 既話係一定救到, 得500, 你expect 個機頭o係到地之前一刻先eject?

btw 訓個晏教食個飯之後多左咁大篇野睇到幾乎暈低左...

[ 本帖最後由 odyssey2007 於 25-7-2010 20:24 編輯 ]

odyssey2007

同埋請記得就算4 秒俾你一個ENGINE 上到full thrust, 唔代表你一有thrust 就即刻可以restore from stall

CWHS

引用:

原帖由 odyssey2007 於 25-7-2010 20:32 發表
同埋請記得就算4 秒俾你一個ENGINE 上到full thrust, 唔代表你一有thrust 就即刻可以restore from stall

小弟...無氣那... 由頭到尾我都係講有chance
小弟前面講左, CF-18是Tailspin致插水, 如maintain yaw, even both eng inop, A/C Perhaps still have 3 Seconds+ Lift to stay in the air.
即Maintain Yaw, 3.X Second Thrust respond to full wet thrust, if更加係tail spin之前能maintain yaw, 之後還有3 Seconds Lift until stall, 就係呢個時間係loss all lift, stall前lift提升 -> A/C Recovery...

小弟唔多講那, 師兄請...

odyssey2007

我神咁早斷左氣la
得一個engine 既thrust推, 咁短時間, f119 都唔係萬能ga..

jackieyue

CWHS 師兄可以PM我MSN嗎???
得閒可以請教o下您!