Gyro From , joined Dec 1969, posts, RR: Posted (14 years 5 months 1 week 16 hours ago) and read 4884 times:
Yesterday I saw a movie on Hallmark in which a bomb was placed on a 747-200. To make the story short, the captain applied the thrust reversers with only the main gear on the ground. Now, I know that DC-10's have a safety feature in which thrust reverse can not be applied unless the nose gear is on the ground aswell. Is the 747-200 able to apply thrust reversers with the nose gear in the air? Why don't all airplanes have the DC-10 feature for safety. Couldn't the Lauda 767 crash have been avoided if it had this feature? Please let me know what other airplanes can apply thrust reverse with only main gear on the ground or while airborne, and which airplanes have the same safety feature as the DC-10...
PhilB From Ireland, joined May 1999, 2915 posts, RR: 13
Reply 1, posted (14 years 5 months 1 week 16 hours ago) and read 4704 times:
It is not necessarily unsafe to apply reverse thrust with only the main gear on the ground. The Trident was certified to apply reverse thrust whilst in the air (with flaps, slats and gear all in configuration). That made landing on Runway 23 at LHR a very interesting experience.
AAR90 From United States of America, joined Jan 2000, 3516 posts, RR: 45
Reply 3, posted (14 years 5 months 1 week 9 hours ago) and read 4654 times:
>If I remember correctly AA allows his MD-80 pilots to use
>the thrust reverser with the nose gear still in the air.
Used to, but not any more. Nose wheel on ground is required prior to deploying reversers for MD80 & MD90 aircraft at AA.
B727, B747, B757, B767, MD80, MD90 and F100 are all _capable_ of deploying reversers with main mounts only on the ground. I do not recall AA's DC10s having anything that prevented reverser deployment prior to nosegear touchdown, but I haven't been on that bird in 13 years.
*NO CARRIER* -- A Naval Aviator's worst nightmare!
Avt007 From Canada, joined Jul 2000, 2132 posts, RR: 5
Reply 4, posted (14 years 5 months 1 week 7 hours ago) and read 4616 times:
I regularly see 747s do this, and when you see how much runway they use up before the nose gear touches down, you can appreciate why.
From a turboprop angle, the dash 8 can reverse pitch while airborne if the pilot pull the safety levers up. This is never done intentionally, as the engines and props overspeed dangerously. There is a warning horn which sounds if he ( or she) does this in flight.
SMcC From United States of America, joined Sep 2000, 48 posts, RR: 0
Reply 5, posted (14 years 5 months 1 week 7 hours ago) and read 4615 times:
Hey cool question!
I'm FO in the MD80, and at my airline they make a strong point in training that after touchdown, you should get the nose on the ground asap (albiet smoothly), and then use the TR's. In the MD80 it is possible for the buckets to contact the runway with the nose in the air and TR's deployed.
Having said that, at my old job, flying 20 and 30 series Lears, we would routinely use aerodynamic braking and idle-deployed TR's. It would save a lot on brake wear and tear. And it was kind of fun too.
Obviously the MD80 and Lear are entirely different in runway performance.
Airgypsy From United States of America, joined Nov 1999, 130 posts, RR: 2
Reply 6, posted (14 years 5 months 1 week 6 hours ago) and read 4597 times:
The 737-300 and up can deploy reversers while in the air if the radar altimeter shows less than 10 feet.
Jack screw driven reversers on fan engines take a bit longer to deploy and spool up so they are given a head start.
Fr8tdog From United States of America, joined Feb 2000, 120 posts, RR: 0
Reply 7, posted (14 years 5 months 1 week 4 hours ago) and read 4594 times:
I reg put the Power levers in beta or reverse when the nosegear is still off of the runway on the saab 340. however it is a balancing act where the nose can slam down on the runway if you dont do it right.... and as for beta while in flight that is a big NO NO for most turbo props...... Eagle did that accidentally and lost an aircraft over it. luckly no one perished on that accident.
basically the prop overspeeded and the engine torqued out of its engine mounts and laid sideways against the wing of the aircraft, rendering it almost uncontrollable.
as a result of that accident the Faa mandated a idle stop gate that only opens from the WOW switch or an idle stop emergency override sw.
which we dont pull for fun ....... the reset is located under the floor. and makes for some unhappy maint personal.
AIR757200 From United States of America, joined Jul 2000, 1579 posts, RR: 7
Reply 8, posted (14 years 5 months 3 days 7 hours ago) and read 4518 times:
What about the DC9? I've seen it many times at DTW, when landing on our shortest runway (little over 8,000ft-enough for a DC9). Once a US Airways DC9 (have it on video also) came in, the nose was kinda higher than previous arriving DC9s (NW), and right when the rear wheels touched, spoilers up and the tr's kicked in, and the nose SLOWLY came in contact with the runway.
Wing From Turkey, joined Oct 2000, 1578 posts, RR: 23
Reply 9, posted (14 years 5 months 2 days 14 hours ago) and read 4495 times:
I've asked this to a MD-88 captain after reading this topic and he told me in MD 88's they don't use the TR's until the nose gear touches down because the it could cause the tail touch on the runway so they put the nose gently but ASAP and use the TR's.In the air there wasn't any additional safety feature he said because TR's handle comes all the way back in 3 stages so its very unlikely to operate them accidently.
DC-9CAPT From , joined Dec 1969, posts, RR:
Reply 10, posted (14 years 5 months 2 days 13 hours ago) and read 4500 times:
Officially, the manual states never activate thrust reversers if the nose is pitched above 8degrees. The reason for that is to avoid the reverser bucket from scraping the runway, not the tail cone itself. Most company policies (from what I have seen) will tell you not to cycle into reverse until the nosewheel is on the ground.
There is no governor, mechanism, actuator etc that prevents the thrust reversers from activating unless there is nosewheel pressure--I think there is a common misnomer about that here.
Gregg From United States of America, joined Jun 2000, 327 posts, RR: 0
Reply 11, posted (14 years 5 months 2 days 12 hours ago) and read 4485 times:
I thought you had to put the nose down on rear engine aircraft since TRs make the rudder close to useless. This is one of the reasons (I think) the AA dc-9 that crashed in Little Rock took the TRs off to try to regain control with the rudder.
Starship From South Africa, joined Nov 1999, 1098 posts, RR: 14
Reply 15, posted (14 years 4 months 3 weeks 6 days 11 hours ago) and read 4417 times:
I am convinced that I read in the Boeing website in the section dealing with the C17 that the thrust reversers can be deployed in flight to enable the aircraft to descend at a rather alarming 20 000 feet/minute.
I also seem to think that thrust reversers on the Il-62 can be deployed whilst the aircraft is still airborne.