|
|
Post by interocitor on Dec 19, 2009 22:31:29 GMT
Hi,
is there a way to reduce the power of the reversers and the wheel brakes?
I can stop the 707 on very small, regional runways...
By the way, is there a possibility to open the rear passenger door and/or service doors?
|
|
|
|
Post by aerofoto - HJG Admin on Dec 20, 2009 4:16:33 GMT
I don't recall ever having heard of an issue like this before .... and in the whole time these aircraft have been available for FS2004 and FSX too. Once again it could be "TECHNIQUE" that's the cause of your issue. Personally .... I've never found the effects of either reverse thrust, or braking, on any of our aircraft to be excessive. I've always found deceleration during reverse to be quite gradual .... and braking action after reverse to be similarly acceptable too. In fact the reverse thrust audio in each of our B707/B720 soundpacks has been, purposely, made to run for approximately 11 seconds (timed by me personally) .... which is the duration necessary for these aircraft to decelerate down to 80-60 KTS after landing at between 150-140 KTS and unassisted by any braking action. A tip ....  Don't apply both reverse thrust and braking action together .... if you have at all been doing that. Also .... when applying reverse thrust don't hold down/depress the "F2" key as some FS instructions advise. Simply ensure the thrust levers are at idle with all 3 landing gear planted on the deck .... THEN .... give the "F2" keyboard command a firm/decisive press.... and then immediately "LET IT GO" again. Holding "F2" down might result in quicker deceleration than is sensible .... I've certainly seen evidence of that in the old days and with earlier FS versions, but, don't know if the same might apply to these aircraft and in FS2004 or FSX too. Don't start braking until "AFTER" reverse thrust is complete. "IF" you fly with a yoke and pedels then it's possible you might have a "SENSITIVITY" issue to be resolved within FS. Ground friction issues, associated with some sceneries, can also result in faster deceleration than is realistic, and in some cases also impose need for higher than is realistic power settings in order to start taxiing, but, I'm not conscious of this ever having been an issue with any of our B707/B720 class aircraft. Other than these advisories .... I've never experienced anything other than what I consider to be perfectly satisfactory/normal, if not reasonably authentic, deceleration performances during reverse thrust and braking with all our aircraft. "SHIFT + E" keyboard commands should open the forward exit door on all our B707/B720 models for you. The port side forward fuselage maindeck cargo doors of all our freight configured (only) B707/B720 models open too on the basis of the old CONCORDE VISOR UP/DOWN commands .... which do also need being manually assigned/activated within FS to then function using "SHIFT+F6" and "SHIFT+F7" keyboard commands. Mark C AKL/NZ |
|
|
|
Post by bluestar on Dec 20, 2009 16:11:27 GMT
I can stop the 707 on very small, regional runways... They don't need a lot of room. At most landing weights and dry runway, they can be stopped in under 3,000 feet. There is a lot of drag with flaps, slats and spoilers plus reversers and brakes. Remember they are designed to stop at V1 while at MGTOW. Depending of the reason for the cut, this abort could be without reversers. Mark may have the charts that will tell the distance required to takeoff at various weights, and that distance should include room to stop at V1. At PANC last week FedEx reporting braking action to the tower - "I had the brakes all the way to the floor and it wasn't even starting to slow down." MD-11s are such great fun. Bill |
|
|
|
Post by aerofoto - HJG Admin on Dec 20, 2009 21:31:52 GMT
I don't have this information at my personal disposal, but, our Harerton DOURADO might like to comment regarding this .... if he cares to ! A V1 "CUT" at MGTOW  .... WOW !!!! .... that would be really "INTERESTING/EXCITING" ;D .... especially on a wet RWY  Give me a "DC10" .... anytime !  Mark C AKL/NZ |
|
|
|
Post by christrott on Dec 22, 2009 2:24:08 GMT
Also, most landings, the engines aren't spooled much beyond Idle Reverse unless they're trying to make the first high speed or it's a short runway. At places like Denver, Idle Reverse with minimal braking is the order of the day. Also, from the guys I've flown with who are "heavy iron" pilots, the "good pilot" technique is reverse only until 100 knots then start "phasing in" the braking. They typically don't like the autobrake either except for actual IMC (instrument) conditions, so this is easy to do. They autobrake will begin phasing in the braking in the "Medium" position around 120 knots and have full braking action at 80 knots, so it starts braking earlier and it does wear the brakes a little faster, but not much. You have to remember - using the reversers doesn't shorten the time between maintenance periods for the engines. Using the brakes a lot shortens the time between replacing them a LOT (as little as 2 or 3 landings if used heavily). |
|
|
|
Post by Harerton Dourado - HJG on Dec 24, 2009 18:57:42 GMT
I'm gonna take a look at my manuals trying to find landing performance info.
Stay tuned.
|
|
|
|
Post by braniffops on Dec 25, 2009 4:55:18 GMT
[/quote] "I had the brakes all the way to the floor and it wasn't even starting to slow down." [/quote] On a contaminated runway, that would be 'braking action nil' - on a dry runway, that becomes a maintenance issue if you can make it to the gate in one piece. In an MD-11, it's just...normal. You said it...MD-11s are so much fun. |
|
|
|
Post by Harerton Dourado - HJG on Dec 25, 2009 15:22:29 GMT
Did a small research on my manuals.
As already said, the most limiting runaway length factor is on takeoff not on landing. So a 707 landing on a "small" RWY should not be a problem. In fact if you search on youtube you'll find a video of a 747 landing on a small airport and (the most amazing) a 727 landing at Meigs. Of course those aircrafts would never be able to takeoff anymore.
As for numbers, a B707-300 (the turbojet version) at max landing weight (almost 210000 Lbs) landing at a sea level field with no wind would require almost a 7000 ft RWY with no antiskid (and possibly no thrust reverses).
For 150000 lbs landing wt, sea level, no wind, a 6200 RWY would be needed (no antiskid and no reverses).
Those numbers refer to minimum RWY length not braking distance.
CAUTION: USE THOSE NUMBERS FOR FLIGHT SIMULATION ONLY!!!!
|
|
|
|
Post by christrott on Dec 26, 2009 3:31:08 GMT
The 727 should have been able to take off out of Meigs at a profitable weight. The reason for this is that the 727 was designed for 2 airports- Midway (before the runway lengthening) and Denver, both per United specifications. The aircraft had to be able to take off of both during the summer at MTOW and land at those airports at MLW. To assist with the landing, the 727 even had an option for nose wheel brakes, which were reportedly so effective, that an Eastern Airlines aircraft flew for several weeks with both main landing gear brakes deactivated and no one noticed the difference. If you look at the video available, he landed shorter than most guys can in a Cessna, so at heavier weights, it still wouldn't have been a problem.
|
|
.... WOW !!!! 
