A safe approach in any type of airplane culminates in a  particular position, speed, and height over the runway  threshold. That final flight condition is the target window at  which the entire approach aims. Propeller-powered airplanes  are able to approach that target from wider angles, greater  speed differentials, and a larger variety of glidepath angles. Jet  airplanes are not as responsive to power and course corrections,  so the final approach must be more stable, more deliberate,  and more constant in order to reach the window accurately. The transitioning pilot must understand that, in spite of their  impressive performance capabilities, there are six ways in  which a jet airplane is worse than a piston-engine airplane in  making an approach and in correcting errors on the approach. The appropriate speeds should be pre-computed prior to every  landing and posted where they are visible to both pilots. The  V$_{REF}$ speed, or threshold speed, is used as a reference speed  throughout the traffic pattern. For example: The approach and landing sequence in a jet airplane should  be accomplished in accordance with an approach and landing  profile developed for the particular airplane.  [Figure 15-23] Figure 15-23.  Typical approach and landing profile. 15-26 36 18 Abeam runway midpoint • Flaps T/O approach V$_{REF}$ +20 minimum • Complete before landing checklist Maximum bank 30° • Clear final approach Turning base • Flaps land Reduce power as recommended in  the landing profile • Start descent V$_{REF}$ +10 minimum Rollout • Reduce speed to V$_{REF}$ Altitude callouts • Stabilized in slot  Touchdown • Extend speed brake Apply brakes • Thrust reverser as required Abeam touchdown point • Gear down DO NOT MAKE  FLAT APPROACH 1,500’ above field elevation Approach Preparations 1. Reset bug to V$_{REF}$ 2. Review airport characteristics 3. Complete descent and begin before landing checklist • Downwind leg—V$_{REF}$ plus 20 knots • Base leg—V$_{REF}$ plus 10 knots • Final approach—V$_{REF}$ plus 5 knots • 50 feet over threshold—V$_{REF}$ • The absence of the propeller slipstream in producing  immediate extra lift at constant airspeed. There is no  such thing as salvaging a misjudged glidepath with a  sudden burst of immediately available power. Added  lift can only be achieved by accelerating the airframe.  Not only must the pilot wait for added power but,  even when the engines do respond, added lift is only  available when the airframe has responded with speed. • The absence of the propeller slipstream in significantly  lowering the power-on stall speed. There is virtually  no difference between power-on and power-off stall  speed. It is not possible in a jet airplane to jam the  thrust levers forward to avoid a stall. • Landing climb—the speed that guarantees adequate  performance in arresting the descent and making  a go-around from the final stages of landing with  the airplane in the full landing configuration and  maximum takeoff power available on all engines. • Approach climb—the speed that guarantees adequate  performance in a go-around situation with an  inoperative engine. The airplane’s weight must  be limited so that a twin-engine airplane has a 2.1  percent climb gradient capability. (The approach climb  gradient requirements for 3 and 4 engine airplanes  are 2.4 percent and 2.7 percent, respectively.) These  criteria are based on an airplane configured with  approach flaps, landing gear up, and takeoff thrust  available from the operative engine(s). Significant Differences