Short Field Performance PDF

 

 

AIRPLANE CONFIGURATION BULLETIN  Technical Summary

Short Field Performance Enhancements  The two new short field performance enhancements are available in two options: Number 0222C472A09

Title Short Field Performance Enhancement

0222C472A10

Short Field Performance Enhancement with Two Position Tail Skid

These options contain enhancements in several separate components: 1. 2. 3. 4.

Speedbrakes Krueger flap seal door Sealed leading edge slats Two position tail skid

 All these components components are included included in the the 0222C472A10 0222C472A10 option, available available on on the 737-800 and -900 minor models. Option 0222C472A09 includes all of the above components except the two position tail skid and is available on all 737NG minor models, although the sealed leading edge slats (item 3) are available only on the 737-800 and -900 minor models. All components taken together yield significant improvements in takeoff and landing performance from airports with runway lengths of 5,000 feet or less. These options also may result in increased payload for these same runway lengths. A more detailed explanation of the revised components is as follows: 1. Speedbrakes The travel of the Flight Spoilers and the Inboard Ground Spoilers will be increased such that they will travel to an equivalent of 60 degrees on the ground. Currently, the Flight Spoiler deploys to approximately 30 degrees on the ground, while the Inboard Ground Spoiler deploys to approximately 52 degrees on the ground (see Figure 1). The effect of the increased spoiler deflection on ground will be increased drag and increased loading on the main landing gear for improved braking performance. These result in a subsequent reduction in landing distance and a reduction in required runway length for takeoff.

 

 

AIRPLANE CONFIGURATION BULLETIN 

Increased inboard ground spoiler o deflection to 60

Figure 1

2. Krueger Flap Seal Door The addition of an actuated Krueger flap seal door will reduce landing distances by improving stall lift characteristics and thus reducing approach speeds. The seal door will be actuated to open the gap between the flap and the engine cowl when the trailing edge flaps are in the Flaps 40 position. The seal door will remain closed at all other flap settings due to the increased drag from this configuration (see Figure 2).

Figure 2

 

 

AIRPLANE CONFIGURATION BULLETIN 

3. Sealed Leading Edge Slats The leading edge (LE) slats will be rescheduled so the slats remain in the sealed (intermediate) position for all takeoff flap settings (Flaps 1 through 25). The LE slats will transition to the Full Extend position for landing flap settings 30 and 40. The trailing edge (TE) flap system will be revised to include flap load relief for flap detents 10, 15, 25, 30, and 40. This enhancement is included in both Short Field Performance options, but is available on 737-800 and -900 airplanes only (see Figure 3).

Figure 3

The intent of sealing the leading edge slats when the flaps are in the takeoff settings is to reduce drag and takeoff speeds, thereby improving takeoff performance.

4. Two Position Tail Skid The final component, available only with option 0222C472A10 on 737-800 and 900 airplanes, is a new two position tail skid (see figure 4). The existing tail skid protects the aft fuselage from the damaging effects of tail strikes if over-rotation occurs during takeoffs. This new tail skid, which extends an additional 5 inches (approximate), will provide protection during landing. It will allow for higher angles of attack during approach, with a subsequent reduction in approach speeds and reduced landing distances.

 

 

AIRPLANE CONFIGURATION BULLETIN 

Takeoff position

~5”

Landing position

Figure 4

 All of the Airplane Flight Manual, Manual, Flight Flight Crew Operatio Operations ns Manual and software software changes to the Stall Management Yaw Damper (SMYD), Flight Management Computer (FMC), Common Display System (CDS) and Enhanced Digital Flight Control System (EDFCS) necessary to take advantage of the enhancements are included as part of these new options. Currently, Boeing is studying the possibility of offering the sealed leading edge slats for takeoff portion of this package for retrofit. Provisions for these options will be provided on all airplanes.