When Boeing designed the 737NG, what factors influenced the change in the flap system?

egid
  • When Boeing designed the 737NG, what factors influenced the change in the flap system? egid

    The early Boeing 737 models had wings with triple-slotted flaps that appeared to be derived from the 727. When the 737 was redesigned as the Next Generation series (dash 600 through 900), these flaps were dropped in favor of a double-slotted design.

    Why did Boeing choose to make this change, and what were the trade offs? Did it impact performance? I had always been under the impression that early 737s were reasonably capable on shorter and rougher runways.

  • One of the biggest differences that you will see between the flaps on the two is that the NG (photo on the right) has continuous span flaps while the classic has split inboard and outboard flaps.

    737 Classic Flaps 737NG Flaps

    Combined with the longer wing on the NG, this gives the new flaps more surface area, so they don't need to be quite as effective. Overall, the NG actually has better performance than the classic, mainly because of the redesigned wing which is 25% larger and has winglets; both of which help out.

    Even though the performance is better with comparable triple-slotted flaps, the double-slotted flaps are lighter (which helps with overall aircraft performance) and have fewer moving parts. This makes them more reliable and they require less maintenance. Most new aircraft designs are moving to either double or even single slotted flaps because of this simpler design and the fact that today's runways don't require the extra performance that would be gained by the more complicated flaps.


    Photo Credits:
    737 Classic Flaps
    737NG Flaps

Related questions and answers
  • The early Boeing 737 models had wings with triple-slotted flaps that appeared to be derived from the 727. When the 737 was redesigned as the Next Generation series (dash 600 through 900), these flaps were dropped in favor of a double-slotted design. Why did Boeing choose to make this change, and what were the trade offs? Did it impact performance? I had always been under the impression that early 737s were reasonably capable on shorter and rougher runways.

  • With the new Boeing 787 where Boeing has provided the capability to swap engine types if the aircraft goes to a new operator quite quickly, I'm wondering if there are any interchangeable flightdecks? Say that you might have a legacy 737 for southwest, but an entirely different cockpit layout (containing the same capabilities) for a company which operates Boeing 787s as well, since the similarities would make training easier. I know a similar project was done on the DC-10s becoming MD-10s, as well as some Saudi MD-90s to be similar to MD-11, but both of these were long-time consuming

  • WWII. They didn't have flight control computers back then, and the only control complaints I recall them having is that early versions had a tendency to flip over backwards when approaching stall speeds, well, that and the ground effects were pretty strong. But, no mentions of going into flat spins when going into hard maneuvers (that I recall). So how do they control that Y axis on flying wings...How do flying wings, like the B-2 Stealth bomber, actually keep themselves from yawing out of control without a vertical stabilizer? For the record, I assume this has to be a simple mechanics

  • As an instantiation, the Boeing 737 persisted in operation and to fly for several years despite rudder issues which had not been safely ascertained and resolved. It's conceivable that flyers who avoided the aircraft had had less probability of injury or death while flying.

  • translate to a deflection of the surfaces, mimicking the "old" mechanical control setup. It is my understanding that this is the design choice of Boeing in its new aircrafts. I do not wish to discuss how Airbus and Boeing made their design decisions, but rather see if there has been performed a study on what interface is preferred by pilots, eventually differentiating among private/commercial pilots...Provided an aircraft with a fly-by-wire system, there are basically two possible choices when it comes deciding how to let the pilots interface with it: rate control / attitude hold: a deflection

  • When I extend my flaps to 10 degrees, what exactly is the 10 degrees measuring? Is this referring to the angle of the flap blades themselves, the new angle of the wing chord, the change in the new critical angle of attack or something else?

  • This comes from a flight simulator experiment ages ago in the Boeing 737.... I'm on the runway. I engage the heading switch, followed by the altitude and thrust. The aircraft lifts off, although hardly in a clean rotation. Now I'm wondering: While it did work in the flight simulator, will the autopilot follow these commands in real life as well if I repeated this in a business or commercial jet? Is there anything stopping the autopilot from engaging a specified altitude or from following instructions which are utter nonsense?

  • beneath the mid-Atlantic. Even after the recovery, there were concerns one of the drives had failed. That ACI episode also mentioned that the Airbus A330-203 in that accident came equipped with a system... technology for maintenance data (and I think I recall hearing Boeing does too), I was wondering if either Airbus, Boeing, or the FAA, plan to facilitate or mandate that the CVR and FDR record...Another enthusiast question. I watch a lot of the National Geographic Channel's "Air Crash Investigation", for better or worse, and it seems accident investigators make tremendous use of the Cockpit

  • In Rickenbacher's autobiography he tells of his flight across the Atlantic in a B-17 after WWII. They ended up running out of gas as I recall, making a water landing in the middle of the ocean. They were stranded for about a month before being rescued. In the early post-WWII era, how was it that they were able to find him at all? What factors contributed?

  • ): a). do I ask approach directly for the IFR clearance, and what is the officially sanctionned phraseology? Also: do I have to cancel IFR when I’m on the ground/see the runway i.e. is the clearance... on the ground/view of rwy)? c). other? BTW: I did read How do you request a "pop up" IFR clearance? . In my scenario I have the time to call FSS, there is no emergency, I'm on flight following...Hi – Here’s the scenario: The flight starts night VFR, with broken ceiling at destination (class C airspace) and expected to improve according to the pre-flight abbreviated briefing. I'm IFR

Data information