WIPERs

[inducedrag]

For years have flown airliners with horizontal wipers now on new aircraft (B787 A350 ) see them vertical any specific reason.

[Piltdown Man]

Less drag when parked.

[safelife]

Less noise when parked.

[BigGeordie]

But if the aircraft is parked you don't have any noise or drag.

I'll get my coat.

[Lantirn]

I think that he is trolling :)

[Denti]

Who? TangoAlpha?

Ok, hat and coat...

[Amadis of Gaul]

Might have more to do with the shape of the windshield.

[Uplinker]

I suspect it is because that's the way it has always been done, until one day, someone said "hang on a minute.......why not park them vertically and save drag, noise and also the torque effect of the drag on the motor and pivot, thereby allowing a smaller and lighter motor/gearbox?"

If aircraft manufacturer(s) were seeking to reduce as much drag and weight as possible in the pursuit of greater efficiency, then even horizontally parked wipers would come under scrutiny.

[Groundloop]

McDonnell Douglas did this on the MD-11 when compared to the DC-10 when they were trying absolutely everything to reduce drag to try and meet the 11's fuel performance guarantees - which it never did.

[FullWings]

I always look out the front window on the 777 and wonder how much energy it takes to push the wipers around the world at M0.84. Probably not much in comparison to the rest of the airframe but as a glider pilot things like that make me wince...

[Amadis of Gaul]

I suppose the other option would be to make them somehow retractable, which actually sounds good, but I imagine that would require pushing all the related complexity of the retraction mechanism around the world.

[stilton]

I thought MD did manage to meet it's performance guarantee's with the MD11, eventually, in fact I think it exceeded them.


Too late by the time they achieved that however, losing the Singapore order was a result of those early shortfalls and it was never a big hit in the passenger world.


Its atrocious safety record didn't help.

[TopBunk]

Full Wings

I always look out the front window on the 777 and wonder how much energy it takes to push the wipers around the world at M0.84. Probably not much in comparison to the rest of the airframe but as a glider pilot things like that make me wince...

Why would you use the wipers at M0.84:ugh: You only need the wipers for a short period during take off and on approach to land.

[FullWings]

Well, that’s the English language for you!

Of course I don’t use the wipers at M0.84 - everyone knows that M0.82/280kts is the limit... ;)

To elucidate: even when not in use, they stick out in the breeze. How much extra fuel is burnt over the lifetime of the aircraft compared to a setup where they retracted? On some cars they retreat into more stagnant air in the scuttle area.

It’s also annoying when the speed and clamping forces allow resonance and the whole thing loudly vibrates for much of the flight.

[Uplinker]

Ha ha Topbunk - you just made my day !

I think that being on the golf course you have just scored a hole in one: foot into mouth, that is. :ok:

[TopBunk]

Fair point - skim reading, I guess.

BTW haven't had a hole in one (on the golf course ;)) since 2008!

[EEngr]

Why would you use the wipers at M0.84Those must be some scary looking bug splatters.:eek:

[fantom]

Wipers.

It is the 11th day of the 11th month.

[tdracer]

Mazda did that with the rear window wiper on my RX-7 30 years ago to reduce noise and drag.
I'm somewhat surprised it's taken the aircraft manufactures this long to catch up :E

[Unregistered User]

If it's a 20 something, hot female, then sure, I'd love to wipe hers.

[oceancrosser]

Mazda did that with the rear window wiper on my RX-7 30 years ago to reduce noise and drag.
I'm somewhat surprised it's taken the aircraft manufactures this long to catch up

No matter how cheap a car you buy, the wipers are far better than on any airliner I have flown. 757/767 wipers. Crap. And lots of times they will not stop when switched off.

[JammedStab]

The first aircraft I flew that had pretty good wipers was the 747-400. At leaast that was my experience. The 777 seems pretty good as well and someone decided to give us a nice intermittent mode. All the truboprops and old Boeings were crap.

[Amadis of Gaul]

In my experience (CRJ, E170/175, A320) they produce more noise than benefit.

[stilton]

Didn't the CV880 /990 use bleed air for rain removal ?


I imagine that was noisy but effective.

[Capn Bloggs]

That squirty stuff in the 146 ran rings around the wipers.

I must admit the Saab has good wiper blades except the speed choices.. off, super fast or having a seizure bat**** crazy fast.
Same here on my non-SAAB! :{

[Capt Fathom]

Never flown any aeroplane where the Wipers actually worked! From GA to multi-million dollar aeroplanes! Just sayin!

[oceancrosser]

Didn't the CV880 /990 use bleed air for rain removal ?

I imagine that was noisy but effective.

DC-8s did have bleed (from the compressors in the nose) for rain removal. Fairly effective, but noisy as hell.

[Uplinker]

The bloke who designed the wipers for the Dash 8 Q400 must have been told at 1658 on Friday "bugger, we forgot the wipers. Quick design something".

:-)

[plhought]

The Q400 wipers are identical to the 'Classic' Dash.

Our outfit they usually try and stop the wipers when they are kind of vertical. Reduces noise considerably.

Still look like they are having a seizure when they are operating

[FixClrEnt]

Many aircraft don't even have wipers. I know that some use a rain-dispersant coating on the 'glazing', so if that works why go to the trouble of fitting wipers in the first place?