Ferret From United States of America, joined Jun 2000, 123 posts, RR: 0 Posted (9 years 3 months 3 days 19 hours ago) and read 9116 times:
I have often seen the strange appendage to the nose gear of the Boeing 717s, MD-80s and MD-90s. It has been identified as a spray deflector.
I am curious why this is needed and why this is the only airframe that seems to need it. I would guess it is to prevent water spray ingestion into the engines, but it seems like that wouldn't be a problem for tail-mounted engines.
BH From United States of America, joined Jul 2001, 525 posts, RR: 1
Reply 2, posted (9 years 3 months 3 days 13 hours ago) and read 8968 times:
You hit the nail on the head of it's use. Recent test have concluded that thier is really no difference on the spray of water with or without the spray deflector.You may start seeing the trend of some of the airlines taking them off.It is also saves a bit of wieght (i guess not that much,but every bit helps).It also saves time on the replacement of the nose gear tires.
From what i am told by the MX guys in the field they take a hell of a beating and always have to be cared for.The Back spray deflectors will stay on.
Dogfighter2111 From United Kingdom, joined Nov 2004, 1968 posts, RR: 1
Reply 8, posted (9 years 3 months 3 days 1 hour ago) and read 8791 times:
Thanks for the info guys,
I was unaware that Concorde was fitted with these prior to the incident. I take it that work was carried out on these after the AF crash. The reason I say that is, that previously I was watching BBC News when Concorde was re-introduced and the new modifications list had the Deflectors on that list.
VC10 From United Kingdom, joined Nov 2001, 1432 posts, RR: 15
Reply 10, posted (9 years 3 months 2 days 20 hours ago) and read 8727 times:
Concorde had water deflectors fitted to the main landing gear and to the nose gear, and they were there to control water from the wheels. They were fitted all the time the aircraft were in service, ie 1976 onwards.
After an incident I believe in the 1980s a recommendation was made that the Main Wheel water deflectors should be strenghtened with metal reinforcing. This was only a recommendation and BA took it up.
Interestingly another rear engine aircraft, the VC-10, had rubber chines moulded into the wall of it's nose wheel tyres, again to try and suppress the water wave from these tyre, and so prevent water injestion by the engines.
DALMD88 From United States of America, joined Jul 2000, 2801 posts, RR: 14
Reply 15, posted (7 years 6 months 2 weeks 2 days 17 hours ago) and read 7778 times:
Quoting Filton (Reply 14): Anyone know what these deflectors are made of? They look like pretty chunky lumps of metal to me - must be very heavy. Someone must have a close up pic
They are made of AL. They are a lot lighter than they look because of that. Most guys I work with hate changing a MD80 nose tire because of the added hassle of the deflector. It isn't that much more work, only two bolts in the back and the one on the axle. Most guys I think are just looking for something to bitch about. Hell, you don't even need to jack the gear. Simply turning the nose gear on a MadDog gets the tire off the ground.
There is also a little spray deflector on the main gear. It's just this batwing looking strip aft of the tires.