View Full Version : (Ex) DC-9 Pilots or Techs - Begging for gen.

19th Mar 2002, 00:49
My friends, (now you know I'm begging!). .. .I'm currently working on a project involving the DC-9 (all variants). I've searched the net high and low for some info about the spoilers and flaps but with no luck. If any ex (or current!) DC-9 pilots or techs are able to tell me about the setup of these systems I'd really appreciate it.. .All I really need to know is:. .Spoilers-. .What are the spoiler functions? ie there are two on each wing, do they both operate as flight and/or ground spoilers? did any of them operate as 'spoilerons' etc. Just basic stuff.. .Flaps-. .What were the flight settings (takeoff and landing etc)? At what stage of the trailing edge flap travel (or detent) is the leading edge slat fully out? Again, basic stuff.. .. .Any help or further info appreciated.. .Thanks a lot.. .. .Skip

Ignition Override
19th Mar 2002, 12:09
It is very late here, but will try to give you a general description. . .. .On the smallest model that we have, the dash 10 series, it has flaps but no slats, Normal takeoff flaps are flaps 20, but with a certain high density altitude (maybe at Denver: DEN) , flaps 10 are used. For landing the dash 10, the first flap setting is to 10 degrees, then 20, 30, 40 and 50 (we now use 40 [max] for noise limits). The other series we have, 30, 40 and 50, use flaps 15 for takeoff, and high density altitudes require flaps 5 (for single-engine second segment climb gradient required, at least 2.5 degrees, I believe). So, on the 30 40 and 50 series, the slat/flap handles always stay screwed together and move as one unit, and stay that way unless there is an abnormal condition. Once the slats are extended, they are always fully out (giving us an illuminated square blue light, whether for takeoff or landing. They require either (normally both L and R) hydraulic system. Pulling back the handle, the first detent is for Slats with 0 flaps, then with flaps 5, 15, 25, 40 and 50. for landing we used 50 years ago, but the FAA re-certificated us to land with 40 flaps, for less noise and go-around power keeps within Stage 3 noise levels. Both flap needles stay very close together, in one gauge. One hydraulic system could operate both slats and flaps on both wings, but at a slower rate than with both. . .. .The spoilers function (two panels on each upper wing, right hydraulic press to both outboard panels and left to both inner panels), beginning with takeoff, as flight/roll spoilers (up to 60 degrees) in order to assist the ailerons' roll rate, starting with about 5 degrees yoke (aileron)/ movement. In flight, the speedbrakes extend in 5 or 6 handle notches up to 36 degrees. When speedbrakes extend inflight and aileron force applied for more than 5 degree roll or more, the downward-moving wing spoilers extend a bit more and the upper-moving wing panels retract a bit. During landing checklist pilot "flow", if handle is armed (straight up) for auto-extension upon landing (only after landing gear are fully extended and speedbrakes are fully down!!), all four panels extend to 60 degrees if either: any two main gear wheels spin up and /or the nose gear strut compresses to the ground-shift mode. Hydraulics and normal AC or DC bus (or both?) power needed for this. . .. .Douglas seems to have preferred a simple system compared to certain Boeing systems. As you might know, the DC-9 has some hydraulic rudder boost, but the basic aileron, elevator and rudder require no hydraulic pressure at all (if speed on short final is 130/135 min. [or Vref, if higher] "until landing assured"). . .. .Hope this helps. By the way, many of these planes will supposedly be with us for a number of years, thanks to various maintenance programs in place. And we have no automation for lateral or vertical navigation, nav freq or course 'auto-tuning'/altitude capture, nor autothrottles, as on most later airline types.. . . . <small>[ 19 March 2002, 07:12: Message edited by: Ignition Override ]</small>

20th Mar 2002, 02:48
Ignition'. .. .That's great stuff indeed, exactly what I wanted.. .Thanks a lot for your time.. .One more thing if you don't mind <img border="0" title="" alt="[Wink]" src="wink.gif" /> . .. .Could you give me some figures for typical takeoff and landing speeds for the average day at sea level assuming max, medium or minimum weight, whichever is handy for you.. .. .Thanks again and all the best to you.. .. .Skip.. .. .As you slide down the banister of life, may all the splinters point the right way.