RMIT Flight Training Shortfield Circuits RMIT Instructor Rating Mass Briefs Issue 1 /2004 Page 1 Brief 14 SHORTFIELD CIRCUITS Aim: To operate safely and efficiently into and out of a field of marginal length, using as little runway as possible. Application: - short/rough strips - ALA’s - obstacle clearance Revision: P-Charts FACTOR TODR LDR Increase Weight ↑ ↑ Increase Headwind ↓ ↓ Increase Temperature ↑ ↑ Flap ↓ ↓ Upslope ↑ ↑ Definitions: Short Field - When the runway length available and/or obstacle clearance gradients are only just sufficient to satisfy take-off and landing requirements. Principles: TAKE OFF Flap - Reduces Vs therefore reducing VTOSS (1.2Vs) - Shorter take off run and distance to 50 ft AGL - Provides better obstacle clearance Power Vs Brakes - Ensures maximum power available to achieve maximum acceleration - Exercise caution on gravel surfaces Climb Performance - Rate and Angle of climb will both decrease APPROACH AND LANDING Flap - Reduces Vs allowing approach at minimum speed (1.3Vs) Power - Allows slower flight on the back of the drag curve - Inboard surfaces (rudder/elevator) more effective Approach Profile -Same flight path flown with a higher nose attitude due less airspeed Landing- Shorter positive flare and touchdown - Use maximum braking as required RMIT Flight Training Shortfield Circuits RMIT Instructor Rating Mass Briefs Issue 1 /2004 Page 2 Brief 14 Considerations: REGION OF REVERSE COMMAND OFF PROFILE – If gross overshoot occurs on approach, be conservative, conduct a missed approach and try again. Don’t push a tight situation. GUSTY CONDITIONS – There is no allowable tolerance below the minimum specified safe speeds. The speeds flown in gusty conditions with fluctuating airspeeds will need to be increased to continually maintain a safe margin over the stall. Therefore, it may not be practical to use shortfield techniques. Air Exercise: Take-off Lower nose FLAP 0o 79 kt (BROC) 57 kt (BAOC) To 200ft or clear of obstacles “40 kt” “51 kt ROTATE” FLAP 10o Power Vs Brakes For soft field apply full back pressure until rotation DRAG (Thrust Req’d) IAS More thrust req’d to fly slower RMIT Flight Training Shortfield Circuits RMIT Instructor Rating Mass Briefs Issue 1 /2004 Page 3 Brief 14 Landing Airmanship: - Smooth coordinated use of controls - Restrict power on gravel surfaces - Higher speeds in gusty conditions may be necessary - If in doubt, go around - Correct handover/takeover procedure - Lookout Apply maximum braking without skidding Maintain full back pressure Target Threshold Speed 55 kt Minimal hold-off and flare Initiate touchdown with idle power 57 kt Increase power as required to maintain speed Normal approach until 300ft Raise nose for 60 kt APPROACH PROFILE DOES NOT CHANGE作者: fantesy5566 时间: 2011-5-4 13:03:50