Hyperveloce

Hi there.
Are pilots flying routinely at moderate flight levels (around 9000 ft) between mountain tops scattered with high altitude glaciers (around or above 9000 ft), subject to occasional blinding (or have their plane lit up) by strong specular sunlight reflections originating from these high altitude glaciers during sunny and clear sky flights ? And in the affirmative, is it a frequently occuring phenomenon ?
J.F.B.

freightdawg

Well, first off, all "flight levels" are above 18,000', and we'd consider 9000' as 'down low'.
IFR airways in mountainous terrain clear the highest peaks by 2000', and flying between peaks would be an unnecessary risk. No, snow glare isn't an issue.

If , however, you speak to our bush flying brethren up in AK, between peaks and over glaciers would be daily normal. Perhaps, some of the guys and gals that land on the glaciers would have glare issues.

Hyperveloce

Sorry for that: my question was ment for small private planes, not airliners, hence maybe not for this forum !

JohnBurke

Some of us consider flight above powerlines to be high altitude. Context.

?

Lots of information asked in that run-on sentence.

Routinely? Depends on the routine. Does the flight have a reason to be there? Does it often have a reason to be there?

Moderate flight levels?

Between mountain tops? Define between mountain tops. Do you mean the surrounding mountains are at the same elevation or higher? Are you referring to passing between to closely spaced precipices or peaks, or are we talking about flight in the general vicinity of mountains with peaks in the area?

High altitude glaciers? Are you aware of many low altitude glaciers? Given that glaciers aren't found in the majority of the US geographical area, and given that much of the US doesn't have terrain above 9,000', and given that the reasons for flying near glaciers or mountainous terrain are limited, you're questioning about some rather specific areas, aren't you? Glaciers aren't normally located near mountain peaks, incidentally, but in the valleys carved...by the glaciers. Glacial deposits can be found in low areas relatively close to peaks in some cases, but glaciers are flows that go downhill and move through the descending valleys and into eventual waterways.

Occasional? How frequent?

Blinding? Is one wearing sun glasses? Is the glacier perfectly flat, or does it have facets or angles, which make any reflection from the sun momentary? what is a "specular" reflection?

Define "frequently."

Perhaps more germane to the discussion is the reason for the question. Curiosity? Writing a novel? Preparing litigation? Reporter looking for a story? Does this concern a recent incident?

Certainly reflections from the surface are possible. I don't know about frequency; it's chance that one ends up in the right position to be subject to such a reflection. More commonly it might be glassy water, rather than a glacier. One passes over a glacier relatively quickly, unless one is doing tours around or landing on the glacier. A reflection from the surface is handled easily; look away. Wear sunglasses. Fly past it. Make a slight turn.

I do a lot of flying in mountainous terrain, and in a few locations where there are glaciers. Being blinded by one has never been a concern. In fact, I also frequently use mirror flashes from people on the ground to guide me to their location: that's a mirror reflecting sunlight at me. Bright, can't miss it, but not blinding. Those flashes occur at relatively short distances in most cases. I don't like bright lights, and I'd prefer not to have the bright light focused on me, but that's why they use flashes and not a steady reflection. They turn the mirror slightly to make the reflection hit me and pass by.

Reflections from the surface, be it a lake or other reflective surface (metal roof, for example) can be very bright, but intermittant, and is are seldom a problem.

Tweetdrvr

The Germans got nothing to do with it. Classic Buford T Justice

http://www.youtube.com/watch?v=cyWVPHoFGJA

Hyperveloce

That's true, I am refering to a precise case which occured a long time ago(24th of june 1947), in Oregon, in the vincinity of a moutain range including the mounts Rainier and Adams (with multiple high altitude glaciers: above 7500 ft, even above 9000 ft for some of them). The pilot (Kenneth Arnold) was at approx 20 miles at the 255° azimut from the mount Rainier, flight level 9200 ft, heading for Yakima. The sun was at 60° of elevation from the 230° azimut. This sighting gave birth to the notion of "flying saucers" and UFOs.
http://www.martinshough.com/aerialph...0analysis2.pdf
We are trying to revisit this case, and in the present case, we are looking for the possibility that nearby mounts and peaks could have created grazing beams of sunlight (specular reflections on the icy slopes) illuminating briefly the plane of K.A. and then nearby birds between him and the mount Rainier (they were crossing his trajectory) at grazing angles so as to make them appear like flashing mirrors (forward gloss).
J.F.B.

DakBroadbent

Doesn't sound like Oregon, for starters.

JamesNoBrakes

Flat light and a few other issues are more prevalent in glacier territory. I've done a decent amount of flying in mountains in variable sunlight and seen things get illuminated before in ways that didn't look "normal", beams of light, certain things illuminated, flat light, "glowing" terrain, etc, but nothing to that extent. It would seem to me that this event is so long ago with so little real data that it's nearly impossible to do anything but guess and speculate, even if you find a scientific explanation that's plausible. Maybe with so much experience and data now we find these things to be fairly obvious in their nature, whereas back in the 1930s with relatively little flying experience and ability to share information, these occurrences seemed much "super natural"?

JohnBurke

Is this a legal case, or part of a UFO story?

Glazing, grazing. Whatever. You're talking about an airplane flying briefly through reflected light. Very briefly.

Is that your writing in the link you provided? It's written in a style and language more appropriate for the mid 1800's. If that's your target audience so be it, but it's not an easy read. Sort of like flossing with sandpaper.

It states: "In one sense it would be true to say that this seminal sighting of nine "peculiar looking aircraft" over the Cascade Mountains of Washington on June 24 1947 (see Appendix 1) needs little introduction." I don't know how seminal it was, but I've never heard of it, so it probably could use a little introduction for the average reader. Perhaps it was written for UFO buffs or x-file fanatics who love that sort of thing...but if written for anyone else, it really does need an introduction.

"...despite more than 60 years of sometimes scholarly debate about this hydra-headed mythological monster." Seriously?

"...that mythology has effloresced..." Now there's a word the average reader uses in every day conversation.

Are you asking questions about angles, ice, and reflection, or are you building a drama so big they'll need to bring back Charleton Heston to play the lead role (damn dirty glaciers...)?

The callair wasn't actually a "mountain" airplane, incidentally. It was just another aircraft, and the company is more famous for their agricultural endeavors, than "mountain" aircraft.

If you're expanding your article or story, more power to you. You can speculate as to what was seen that day, but that's about as far as you can go.

I'd say that many of us have seen things in flight we couldn't explain, but that does 't mean they're UFO's, and and it doesn't mean they're not. I've seen traffic on the North Atlantic routes that was obviously present, but not necessarily where it should have been. I couldn't identify it, but I'm sure someone else could.

A standing NOTAM has been out for unidentified military traffic south of Iran for some time now. Is it military? Is it a UFO? Who cares? It's traffic. Back at the time of Project Bluebook, it was quite the rage for the public, and it was an annoyance and a security concern for the military. Flying saucers were a hot topic. Today? Not so much.

Phoenix is famous for UFO sightings, but the truth is that the ones you'll see on the TV shows happen every night. Stand on a mountain and watch the aircraft lined up on the arrival. Not really such a great mystery after all.

I once flew a three-ship formation down across Arizona and into southern California. At one point one of us noticed a silver metalic object that didn't at all look like an aircraft, well above us, which appeared to be moving west. One of us attempted to climb up to it, but gave up. My best guess; some kind of balloon. Probably a mylar balloon. I never heard more about it. The appearance of westward movement was probably illusion, and it was probably a lot farther than we thought. Passing interest.

We see things from time to time. Sometimes we know what they are, sometimes not. Who can say, after its gone? I watched a meteor shower one night over Pakistan as I headed up into Afghanistan. I think I counted over a hundred. I'm sure there were many more. Under the right atmospheric conditions, who knows what someone else might have seen?

Yes, there are reflections off glaciers, off aircraft, off water, and even off the atmosphere. Shadows form, haze makes distances seem greater. Parallax makes one see things differently than they are, or at least differently than others see them.

You read the story, you see a multi-headed hydra monster. I read it I see a guy who saw something he couldn't explain. I suppose if we all get hung up on things we can't explain, we'll be hung up for a very long time. I exercise my one, sole superpower, which I like to call "I-dont'-care," and move on. The power of apathy is a great enabler, as it's the power to ignore.

Good luck with the project.

Hyperveloce

No, this is not a report written by me (I am not able to write in English with this degree of... sophistication: I am French)... A Scottish friend of mine is responsible for this ) But the account is quite accurate and complete.
Thanks for your contribution anyway.
I've run simulations on DEMs (digital elevation models) of the area and found suitable (so as to reflect sunlight toward the observer) areas on several mounts in the vincinity. Still trying to credit with pilots the possibility of strong sun glints from sloppy, high altitude glaciers.
J.F.B.