Why do jets have windshield wipers?

ebykowsky

ebykowsky

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If 172's don't need them because the wind blows the rain off, why do jets that go 2-3 times as fast?
 
For taxi, at speeds where the 172's propwash would blow rain off the windshield.
 
Also, on some jet aircraft, the airflow over the windshield at approach speeds (read: high angles of attack) isn't sufficient to clear the windscreen. These aircraft will have either windshield wipers or bleed air ducts to clear the windshield during the approach.
 
DaleB said:
For taxi, at speeds where the 172's propwash would blow rain off the windshield.
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So I was thinking that too, but do multi engine prop planes like Barrons and 421s have wipers?
The angle of attack explanation is good as well-never thought of that.
 
ebykowsky said:
So I was thinking that too, but do multi engine prop planes like Barrons and 421s have wipers?
The angle of attack explanation is good as well-never thought of that.
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Depends on the plane. The Navajo had a left windshield wiper, so did the cheyenne. Commander had both sides. 310 doesn't. Keep in mind that not all planes have all features. For example our 310 has prop heat (factory). The boots are aftermarket but are wings and horizontal tail only, and no windshield heat. Many 310s had no boots. Even many Aerostars had no boots.
 
By the way, the 310 without windshield wipers is a pain to taxi in rain. Would be nice to have, but I wouldn't sacrifice the 1-2 kts cruise speed and 5 lbs for them.
 
Taxi and actually on approach speeds in heavy rain it does help.
 
I have them on my King Air and have only found them useful for taxi in rain, but in that case, very helpful. Haven't been on an approach in heavy rain to try them.

Best,

Dave
 
IIRC the wiper on the Navajo is also listed as required equipment for FIKI
 
It's a quicker and safer means of etching the windscreen than getting out your bottle of Windex and a paper towel to do donuts thru the viewpoint
 
Depends on the aircraft & windshield design. I've used the wipers on a Black Hawk plenty of times in heavy rain in forward flight. Wouldn't be able to see a thing without them.
 
Ted DuPuis said:
By the way, the 310 without windshield wipers is a pain to taxi in rain. Would be nice to have, but I wouldn't sacrifice the 1-2 kts cruise speed and 5 lbs for them.
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Is there a RainX equivalent for the plexiglass used in airplanes?
 
Skylane81E said:
IIRC the wiper on the Navajo is also listed as required equipment for FIKI
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I always wondered why they never ripped them out of the planes I fly, but if that's the case, it make sense why now.
 
CJones said:
Is there a RainX equivalent for the plexiglass used in airplanes?
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I don't know, but good question. If there is, I should buy it.
 
On transport jets using windshield wipers on approach improves forward visibility substantially. Also taxing around the airport they are needed.
 
Ted DuPuis said:
I don't know, but good question. If there is, I should buy it.
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We always cleaned the plexiglass windhields with Lemon Pledge, non-abrasive and the water seems to bead up and run off. I use it on the 182 and I get some odd looks at the FBO, but it works! :D
 
N747JB said:
We always cleaned the plexiglass windhields with Lemon Pledge, non-abrasive and the water seems to bead up and run off. I use it on the 182 and I get some odd looks at the FBO, but it works! :D
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Pledge is an old car show trick to repel dust at shows.

It's not a very durable finish though so it doesn't last long.
 
If planes with a front propeller don't need wipers because the propwash blows water off the windshield, then is it fair to say that every plane, jet or otherwise, without a front prop would benefit from wipers?
 
NoHeat said:
If planes with a front propeller don't need wipers because the propwash blows water off the windshield, then is it fair to say that every plane, jet or otherwise, without a front prop would benefit from wipers?
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I'd say that, if nothing else they'd benefit for taxi.
 
NoHeat said:
If planes with a front propeller don't need wipers because the propwash blows water off the windshield, then is it fair to say that every plane, jet or otherwise, without a front prop would benefit from wipers?
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We have an artificial prop (a fan) but I can't recall using it in flight and only rarely on taxi. As picky as they are about what goes on the windshield I can't imagine using wipers.
 
I don't use the wipers on my Mazda 6, except during taxi. At cruise speeds of 65 MPH, the wind is sufficient for keeping the windscreen fairly clear--even without a prop. Anyway, my headlights scare any traffic right out of the way.

Forward visibility is overrated.
 
For the same reason cars do.
 
spiderweb said:
I don't use the wipers on my Mazda 6, except during taxi. At cruise speeds of 65 MPH, the wind is sufficient for keeping the windscreen fairly clear--even without a prop. Anyway, my headlights scare any traffic right out of the way.

Forward visibility is overrated.
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My magnum is the same way, except for mist no wipers needed over 40.

Other side of the coin is my Saturn, it needs the wipers on at any speed even if it is just humid out:rofl:
 
Skylane81E said:
My magnum is the same way, except for mist no wipers needed over 40.

Other side of the coin is my Saturn, it needs the wipers on at any speed even if it is just humid out:rofl:
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The wipers on my Mitsubishi become somewhat ineffective above 80.
 
JHW said:
nu-finish in the orange bottle. When you fly through a cloud, the squashed bugs slide off
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Every time I wash the plane all the plexi gets buffed inside and out with NuFinish. It's a great product.
 
The thing that struck me about the windshield wipers for jets is how thick they are, the blades are like an inch and a half plus long. I sold a few for a 727 for about 300/ea as removed a few months back. The motors, as removed, fetch at least a grand or more for old models alone. If you find anyone who actually flies the things, that is!
 
Velocity173 said:
Depends on the aircraft & windshield design. I've used the wipers on a Black Hawk plenty of times in heavy rain in forward flight. Wouldn't be able to see a thing without them.
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I have used them often on the SR71 for the same reason. At those speeds, forward visibility is important.

Interesting side note, the windshield wipers on the SR71 are identical to the 60s VW bug. You can save a few dollars if yours wear out rather than pay for the up charge for the certified versions.
 
PPC1052 said:
I have used them often on the SR71 for the same reason. At those speeds, forward visibility is important.

Interesting side note, the windshield wipers on the SR71 are identical to the 60s VW bug. You can save a few dollars if yours wear out rather than pay for the up charge for the certified versions.
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Rain at 80,000 ft? No.

Bugs hitting the windscreen? Yes. :)
 
Windshield wipers need glass windshields. They'd scratch plastic. So little airplanes don't have them.

Dan
 
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