What is the purpose of the storm window?

[Fred Gassit]

I have wondered for many years about the purpose of the storm window on some smaller planes having personally used it for ventilation occasionally on hot days.
Funny thing is nobody has ever been able to tell me why they are there.
I'm sure someone here will know.
Regards

[barit1]

If you ever had to land with an obscured windshield, it would be pretty obvious why it's there. Every plane I've ever seen has some cockpit window that can be opened - for visibility, ventilation, smoke removal, shouting to ground crew, etc.

[downsouth]

Yea, no wonder its usefull... The question is: Why is it call STORM WINDOW?? That's something I asked myself many times...

DS

[TyroPicard]

barit1..
Have you ever seen a 747?
TP

[411A]

Or...a TriStar?
No FD windows needed, nor desired, thank you very much.

Now, as to the term 'storm window'...it was coined by a small airplane pilot long ago, who needed to land in a severe rain storm, where visibility was totally obscrued out the front.
On larger transport aircraft (pistons, turbopropellor types) they are referred to as DV (direct vision) windows.

Next question?...:}

[Fred Gassit]

Thanks, thats what I suspected, most planes I fly with window wipers dont have'em , they have a whisky hatch instead, how about the origins of that name?

[airsupport]

On some Aircraft types also called a CV (clear view) Window. :ok:

[barit1]

TP & 411A -

Sorry - my 1011 & 747 background is rather limited & a long time ago. :O

How are the aforementioned contingencies handled?

[Clarence Oveur]

I suspect the ability to open windows on large commercial aircraft, has more to do with jumping out of them than anything else.

[barit1]

I distinctly remember the 747-200 has a cockpit roof hatch with escape ropes - that must be quite a ride sliding down from that height!

[IGh]

This may not be obvious: the biggest risk of inflight fire is eventual Loss of Control.

Fatal fire and crash, TWA Lockheed Constellation NC86513 Star of Lisbon, ... near Reading, PA 11Jul46. Sixteen minutes after T/O (during practice engine-out ops) an F/E smelled odor of burning insulation; when he opened cockpit-bulkhead Door to cabin blast of heat and dense black smoke poured into cockpit. Smoke in cockpit inhibited pilots Nilsen and Brown from seeing panel. Cockpit crew-hatch was opened to clear air, but this only drew more smoke into cockpit. IP Brown opened right sliding window; Brown put head out window and flew aircraft to emergency landing (smoke created danger of losing control). Landed 2 miles NE of airport, skidded 1000' across hay field. Tanks ruptured, fuel fire. Only IP-PIC RF Brown survived (burned, amputee) ...


Varig 820 / 11Jul73,
Clipper 160 / 3Nov73,
Air Canada 797 / 2Jun83

In the Varig, Pan Am, and Air Canada cases, and in others, the smoke accumulation in the cockpit became so thick (and physically irritating) as to motivate pilots to open their cockpit Sliding Window. In the case of UA 823 / 9Jul64 the smoke/fire in the cabin motivated a passenger to open the Over-wing Exit while still in flight.

[Basil]

On light a/c, e.g. Aztec, if main door opens in flight, opening panel on LHS equalises pressure and assists with closing door.
May also be used as urinal - by chaps and, possibly, by highly skilled chapesses :)

[AirRabbit]

I distinctly remember the 747-200 has a cockpit roof hatch with escape ropes - that must be quite a ride sliding down from that height!
Well, they aren’t “ropes” … they’re inertia reels, unwinding ribbon tape – and, at one time (perhaps still?) that ribbon was actually metal. It was always A LOT more preferred to be first out, because later users had to contend with the already dispensed “ribbon” from the previous users, and getting sliced on the way down was not a particularly attractive prospect, particularly noting what part of your anatomy was most vulnerable!

But you are right about it being “quite a ride.” Those of you old enough to remember, may be familiar with the old Disney Land Park ticket structure … using that reference we affectionately referred to the “B747 escape system” as “an E-Ticket ride!”

[barit1]

Yeah - I knew they were inertia reels - I was oversimplifying. :ouch:

[safetypee]

The background relating to the question and some of the answers are in CS25 (FAR25); also see part 23 for the smaller aircraft.

CS 25.773 Pilot compartment view.
(b) (2) No single failure of the systems used to provide the view required … must cause the loss of that view by both pilots in the specified conditions.
(3) The first pilot must have –
(i) A window that is openable under the conditions … when the cabin is not pressurised, … or
(ii) An alternative means to maintain a clear view under the conditions.
(4) The openable window specified in sub-paragraph (b)(3) of this paragraph need not be provided if it is shown that an area of the transparent surface will remain clear sufficient for at least one pilot to land the aeroplane safely in the event of - … …

CS 25.775 Windshields and windows
(e) The windshield panels in front of the pilots must be arranged so that, assuming the loss of vision through any one panel, one or more panels remain available for use by a pilot seated at a pilot station to permit continued safe flight and landing.
I suspect that many years ago the conditions which caused a loss of view were associated with storms, ice etc; thus the term ‘storm window’. The regulations in those days might have even used the term.
More recently the window was known as a 'direct view' or 'clear vision' window, and even more recently, particularly when 773 (4) is used, then the term 'escape' window may be used.

[old,not bold]

I've always called it the DV Panel...DV for Direct Vision, I was told, but I haven't a clue why "Panel".

There to use for landing if the main windshield becomes opaque for any reason, I was also told, although it always seemed to me unlikely that one could see much ahead through it on most aircraft I've flown.

Mostly used, on light aircraft, for squeaking "Clear Prop", isn't it?

[108.9]

Im confused here.

Are we refering to the little window on the RHS and/or RHS of light aircraft doors that are about the size of an envelope and fip down or slide across?!

How can one use this to see ahead if the windscreen is obscured?

[airsupport]

Talking about a window in the cockpit that can be opened to see out of.

Not sure about light aircraft, but most airliners have them.

On DC9s for example, there is a CV window on each side that opens inwards and then slides back out of the way, this can be used to see forward if you cannot see through windscreen, also on the DC9 it is big enough to escape through, or as I have done many times open to clean the windscreen. (on the ground). :ok:

[Centaurus]

Now, as to the term 'storm window'...it was coined by a small airplane pilot long ago, who needed to land in a severe rain storm, where visibility was totally obscrued out the front

I don't know about a small aeroplane pilot inventing the term but I do know we called them storm windows on the Dakota and Lincolns I flew in the early Fifties. They were mainly there if ice obscured the main windows and in fact it was a normal design feature of old British aircraft and some American types as well. Circling in blinding rain when the wipers simply could not cope, it was SOP to open the storm window to improve forward vision and it was very effective although a trifle noisy with four RR Merlins on the wings.

The sliding cockpit windows installed on the 737 can also be used in the open position for not only smoke egress but if you have to land and vis is severely restricted through the forward screens. The wipers on the 737 are inefficient in blinding rain and if the chips are really down it may be the only way to get the aircraft on the ground by peering through the open window. The FCTM covers this.

[ManaAdaSystem]

I've landed the 737 in heavy raiin on many occations, and the thought of opening the cockpit window never occured to me. Neither is it suggested to do so in my FCTM.

Visibility in the 737 is mainly determined by the state of the rain repellant coating. The window vipers are a joke.

[jammydonut]

I would think the "storm window" is somehow connected to the nautical terminology used in the early days of aviation:cool:

[Piper19]

-Storm windows are there indeed if your windshield gets iced up and you can't see the runway. That's why most small aircraft with IFR capability have them. With cessna 152 e.g. you're not allowed to fly in icing conditions (no anti-ice installed) thus no storm window installed.

-direct vision panel serve the same purpose, except it's really located in the front of the pilot's vision. The BN Islander is one example i can think of.

-big airplanes usually have windshield and window heating, thus no such panel required.

-an airliner can be flown with windows opened. I've seen this done on a B777 and an A320 in hot climates. And there is a youtube video of such an event also.

[777fly]

If you have seen the DV window opened in flight on either a 777 or an A320 in hot climates,you were dreaming. These aircraft have extremely efficient pressurisation and air conditioning systems, capable of coping with extremes of temperature. The DV window would only be opened in an extreme emergency involving smoke in the cockpit. I am not aware of a single incidence of this situation, on either aircraft. In fact, I am not even sure that the A320 windows can be opened in flight, I do not fly it......

[airsupport]

Nice save 777fly, I saw the original post. ;)

While I doubt very much any Pilots would have those windows open in flight, except in an emergency, I have routinely seen them open on the ground while taxiing out on DC9s, especially when we were doing a max weight take off and had the packs off, MAYBE this is the sort of thing Piper19 has seen.

Incidentally Piper19 your comment about windscreen/window heating is incorrect, these Aircraft still have CV windows (well some do anyway), what if the heating is U/S, the windscreen is shattered or just zero visibility through it, I had a DC9 one day that hit a large Brolga (nearly as big as an Emu or Ostrich), that CV window WAS used that day. :ok:

[Centaurus]

I've landed the 737 in heavy raiin on many occations, and the thought of opening the cockpit window never occured to me. Neither is it suggested to do so in my FCTM

The opening of the side windows in the 737 is a fall-back if you have lost all forward vision, have insufficient fuel for diversion and you have to get it on the runway or crash. Read B737 CL FCTM page 8.30 date October 31, 2006. And if you do not have that publication here is what it says:

"if needed, the windows may be opened in flight, after depressurising the airplane. It is recommended that the airplane be slowed down since the noise levels increase at higher airspeed. .....because of aircraft design, there is an area of relatively calm air over the open window. Forward visibility can be maintained by looking out of the open window using care to stay clear of the airstream."

There is a charge of ten guineas for this information from Centaurus payable to an account in Nigeria... PM me for details:ok:

[IGh]

Regarding the restrictions against opening the "Clear View Window" --

Rummaging around out there on the coffee table, I did locate that issue of _Air Line Pilot_, of July 1948, pg 7:

"In lieu of adequate masks and until such are provided, it is advisable to have the fire axe handy to punch a hole in the forward windshield to provide sufficient oxygen. Do not open the clear view window as you will suck more CO2 into your face. Remember that punching a hole in the forward shield should be a last resort...."


[There had been several inflight fire mishaps, which led to installation of extinguishers; these engineered safety features (the CO2 gas) proved fatal in later use, where pilots did not yet have O2 masks.]

[perkin]

because of aircraft design, there is an area of relatively calm air over the open window

Ingenious! I was wondering how you could poke your head out without being decapitated by the wind!

[john_tullamarine]

to have the fire axe handy to punch a hole in the forward windshield

not on any modern aircraft, I suggest ... unless you back up the axe with a few heavy calibre rounds ...

how you could poke your head out

I don't think that is the idea ... more a case of having the hole through which to look .. might take some yawed flight to make it work, depending on Type, but the aim is a successful recovery .. rather than one's normally elegant landing.

[ChristiaanJ]

Concorde had DV windows. Might have helped during a curved approach if the nose didn't come down properly... although that's never happened due to the belts and braces and bit of string and knife in your pocket approach, that was taken for that particular bit of engineering.

But for those of you who remember the Concorde first days, and final days... they were great for a bit of flag waving... :)

[perkin]

yawed flight to make it work

Ahhh, equally ingenous...not being a flier myself, I hadnt considered that the aircraft could be yawed...thanks for the insight, I had been wondering since this thread started, but didnt like to poke my SLF nose into it too much :)

[john_tullamarine]

... sir, your SLF goodself is most welcome to participate in this particular sandpit.

The aim here is information transfer and interested/interesting discussion .. we aren't too fussed as to who does the asking ...

So far as the yawed flight is concerned, one might have to fly a sideslipping approach so that the aircraft tracks a straight line to the runway while pointing somewheres else .. so that driver Jim/Jane can keep an eye on where he/she is trying to go ...

[Piper19]

allright maybe I'm not following the right term of "DV window" here. I was referring to it as a small sliding piece in the window pane, but apparently it is something else? Can anyone put up a picture for me then, or a link?
Anyway here a video of a 739 flying with the side windows open: http://www.youtube.com/watch?v=rZhOGmo3fC8&feature=related

[belloldtimer]

COMMON GUYS, THIS IS SIMPLE.......


HOW ELSE ARE YOU GOING TO SIGN THE FUEL BILL?

HOW YOU GONNA MAKE SURE THE ATTENDENT CHECKS THE OIL AND TYRE PRESSURES?

:ok:

[airsupport]

allright maybe I'm not following the right term of "DV window" here. I was referring to it as a small sliding piece in the window pane, but apparently it is something else? Can anyone put up a picture for me then, or a link?
Anyway here a video of a 739 flying with the side windows open:

Piper19,

The link you posted shows the window open. :ok:

[airsupport]

http://img339.imageshack.us/img339/2255/dc9si3.jpg

This is the DC9, the 3 "windows" from the front are the fixed "windscreen" (you can see the wiper on it, then the "cv window" which opens inwards and slides back out of the way, then at the rear (and above too) a "fixed window". :ok:

[Centaurus]

Quote:
yawed flight to make it work

Ahhh, equally ingenous...not being a flier myself, I hadnt considered that the aircraft could be yawed...thanks for the insight, I had been wondering since this thread started, but didnt like to poke my SLF nose into it too much

I doubt if yawing to get a better look out front will help except get a blast of 140 knots air into your eyes due to the angle of airflow caused by the yaw.

[perkin]

sir, your SLF goodself is most welcome to participate in this particular sandpit

Why thank you, kind fellow! This sandpit surely must take the award for being the friendliest on PPRuNe! :ok:

[av8boy]

The windshield panels in front of the pilots must be arranged so that, assuming the loss of vision through any one panel, one or more panels remain available for use by a pilot seated at a pilot station to permit continued safe flight and landing.

Or observing vegetation…

Not precisely on-subject, but these two accidents have stuck in my head since I first read the reports ages ago. This thread reminded me of them. When you’re trying to find the localizer and foliage appears outside your window, well, that’s probably a surprise... :eek:

January l2 1937, Newhall, California (just southeast of the Magic Mountain area in Los Angeles County), a Western Air Express Boeing 247B descending into Burbank:

The pilot stated that when the range signals came on, he heard three distinct Ns and realized that he was east of his course and probably over the higher mountains to the southeast of Saugus and east of Newhall pass. According to the testimony of the pilot, he immediately started a turn in order to get over lower terrain and back on course. At almost the same moment, he stated that he sighted two bushes out of the left window which was open and knew that a collision with the ground was imminent. (Original US CAA report of 12 May 1937 does not carry a File Number)

Yup. It was.

January 5, 1941, in almost exactly the same place as the other accident, a United Airlines Lockheed Loadstar also descending into Burbank:

The captain later stated that he became concerned over the situation, especially since he did not receive a signal from the Newhall Pass Fan Marker, and that he then thought it advisable to discontinue the instrument let-down. He had by this time leveled out at 4500 feet. He glanced out the window and saw something dark which, he subsequently stated, he thought was a break. He glanced at the altimeter which read, so he states, 4200 feet and pulled the nose up. He opened his side window for better vision but could see nothing. He then looked ahead and, at that instant, saw a tree in line with the left motor, just as the aircraft struck it with the left propeller and landing gear. He pulled up rapidly and opened the throttles wide. The first officer raised the landing gear. After the initial zoom and subsequent leveling off, the captain turned right to 270 degrees and held that heading until he had reached an altitude of approximately 5500 feet. He then turned left to 180 degrees and climbed straight ahead until he was on top of the overcast. (US CAA File No. 331-41)

Again, I admit this isn’t a CV window story, but these two accidents always give me shivers…

Dave

[Spooky 2]

You never had the pleasure of flying the Lockheed L1011 then?