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Unread 07-06-07, 01:50 PM
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travis travis is offline
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Join Date: Sep 2003
Location: KFWS
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travis is an unknown quantity at this point
Ill throw in my two bits...

In my opinion the proper rotation speed for a "normal take off" is at about 80mph (70kts) with a target pitch attitude of about 3-6 degrees depending on weight and density. A nice gentle increase in pitch will allow the aircraft to become air bourn and accelerate at the same time. I then hold pitch until blue line (Vyse "best rate single engine" Not to be confused with V2 "best angle of climb one engine out" more like red line). When an emergency return to the runway is no longer possible gear up. Generally at minimum 400' AGL flaps up, the whole time accelerating to 130mph (115kts) cruise climb. The last part is the power reduction at or above TPA with no less than 130mph.

A note on takeoffs. In a transport category aircraft (FAR part 25) we set (through manufacturer certification and or standard operating procedure) decision and abort criteria. A typical takeoff briefing in a Lear 45 is "will abort for anything before V1." Note that by certification V1 is the go point, at that speed there is no aborting! In the normal category (FAR part 23) there is no predetermined criteria. This allows us as PIC to determine when we will abort. The idea being that in a single and engine failure will result in stopping the airplane from any point in the flight. In the 337 as in any multi engine aircraft the key is getting to Vxse. Of course Cessna didn’t bother to mark that for us on the ASI So blue line is the place to be. The faster you get there the better your odds of having a successful emergency procedure!

Something to remember about recrip engines is that at wide open throttle the engine is running very rich and there fore very cool. The number one time and place for engine failure is on initial power reduction when you come out of WOT and begin running leaner. With that in mind I climb WOT to altitude and generally leave it there until my decent. Props should be reduced to the green to save the cylinders, but I leave the throttles wide open (this obviously will not work for turbo supercharged engines.) This and my minimum AS allows me to climb with the cowl flaps closed (or partly closed when it’s hot).

When I’m entering the pattern I always go 1/3 flaps first generally before joining the downwind. Gear down crossing the mid field or overhead if I’m crossing the runway. Then slowing for flaps as needed to be configured and on the blue line on about a 1 to 2 mile final. Rember the blue line is Vyse it is only there if you are going to be climbing on one engine! It really is not a speed to cross the fence at in other words once landing is assured a better approach speed is more like 85mph (74kts). For those of us who are interested in the transport category we don’t approach at Vapp (best engine out angle of climb approach configuration) we approach at Vlnd (often times modified for SOP or WX) so that we don’t pay a landing distance or break energy penalty.

_travis
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