Flat light recomendations
- Thread starter Hardhead
- Start date
cubdriver2
FRIEND
upstate NY
Those cheap Blue blocker glass worked when ridding a sled. Red lense safety glasses they sell at TSC work for flat light and a little advantage when scud running
mvivion
SPONSOR
Bozeman,MT
IF there is enough light for colored lenses, I found that Serengeti’s worked well all year. They darken in brighter light.
But true flat light is nothing to trifle with. I was taking a recurrent flight check in a 185 of skis near Fairbanks, mid winter. Really low sun line and light snow.
Check Airman pointed out a lake and told me to land there. I looked it over and put down trackside , came back around and landed the tracks. Check pilot said, okay, taxi back and takeoff same direction I’d landed. I did, turned around and as we approached the next turn around, my heart sank. Not many feet to the left of my approach was a huge beaver house.
Neither the Check Airman nor I had seen the thing as we were landing. We figured that was enough pioneering for the day and returned to civilization. In twenty winters in FAI, I became VERY careful of “flat light”.
it really depends on how far north you are in AK. But if very far, be VERY careful if landing off airport (or on airport, for that matter) in mid winter, pay really careful when off airport. True flat light can be really scary stuff.
MTV
But true flat light is nothing to trifle with. I was taking a recurrent flight check in a 185 of skis near Fairbanks, mid winter. Really low sun line and light snow.
Check Airman pointed out a lake and told me to land there. I looked it over and put down trackside , came back around and landed the tracks. Check pilot said, okay, taxi back and takeoff same direction I’d landed. I did, turned around and as we approached the next turn around, my heart sank. Not many feet to the left of my approach was a huge beaver house.
Neither the Check Airman nor I had seen the thing as we were landing. We figured that was enough pioneering for the day and returned to civilization. In twenty winters in FAI, I became VERY careful of “flat light”.
it really depends on how far north you are in AK. But if very far, be VERY careful if landing off airport (or on airport, for that matter) in mid winter, pay really careful when off airport. True flat light can be really scary stuff.
MTV
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BC12D-4-85
SPONSOR
Fairbanks, AK.
Simplest are amber colored shooting or snomachine/skiing lenses.
These are the traditional flat light glasses and color> https://www.vintagesunglassesshop.com/ray-ban_ambermatic.html While they do work as promised outdoors, the windows in cockpits don't pass the required light spectrum to make them darken much in flight.
Today they offer these photochromic (or transition) lenses in plain or prescriptions> https://rx-safety.com/2013/10/transition-brown-vs-grey/ I've used the brown models as trifocals year round for a long time, and find them to work well in flat light. If in bright sun then something like B&L's G15 dark lenses filter better and are easier on the eyes.
Be careful with vertically progressive prescription lenses like Varilux when flying. While easier than bi or trifocals, they can offer blurred images when quickly looking off center w/o moving your head.
Gary
These are the traditional flat light glasses and color> https://www.vintagesunglassesshop.com/ray-ban_ambermatic.html While they do work as promised outdoors, the windows in cockpits don't pass the required light spectrum to make them darken much in flight.
Today they offer these photochromic (or transition) lenses in plain or prescriptions> https://rx-safety.com/2013/10/transition-brown-vs-grey/ I've used the brown models as trifocals year round for a long time, and find them to work well in flat light. If in bright sun then something like B&L's G15 dark lenses filter better and are easier on the eyes.
Be careful with vertically progressive prescription lenses like Varilux when flying. While easier than bi or trifocals, they can offer blurred images when quickly looking off center w/o moving your head.
Gary
BC12D-4-85
SPONSOR
Fairbanks, AK.
Another aspect of flat light is sunlight direction relative to flight. Surface irregularities create shadows providing the light is strong, not axially scattered too much by low clouds, or not obscured by precipitation. If landing with the Sun's rays shadows may not be seen..they're on the other side of any bumps. Fly around in a circle over the intended LZ and see if lumps and bumps are more pronounced in a certain direction. Forget polarizing lenses as they give a lack of surface definition on snow and water.
Here's a tragic CFIT on Alaska's North Slope in flat light with cloud cover. Hight time pilot turned and hit. Passenger survived. Note the dry grass but lack of horizon definition. The shore of the dry lake bed is dimly visible in the distance.
Gary
Here's a tragic CFIT on Alaska's North Slope in flat light with cloud cover. Hight time pilot turned and hit. Passenger survived. Note the dry grass but lack of horizon definition. The shore of the dry lake bed is dimly visible in the distance.
Gary
Attachments
Speedo
FOUNDER
TN
Here’s an earlier thread on Method 7 glasses and flat light. When I was flying in the Y-K Delta I tried several different types of glasses and found those with a rosy-brown tint worked best for me. Blue blockers were good but not as good. Vuarnet glasses were developed in France for skiing, and some of their lenses do very well in flat light. Although I’ve not used them for flying, I suspect they’d do very well.
While we’re on the subject of glasses, these days I’m flying a PC-12 and using a pair of progressive lenses which have been specially tinted by Sky Sight Vision. The upper part and sides of the lenses are tinted, while the rest of the lens is untinted. This makes it significantly easier to read the panel instruments and approach plates, yet you still get good relief from bright sunlight.
While we’re on the subject of glasses, these days I’m flying a PC-12 and using a pair of progressive lenses which have been specially tinted by Sky Sight Vision. The upper part and sides of the lenses are tinted, while the rest of the lens is untinted. This makes it significantly easier to read the panel instruments and approach plates, yet you still get good relief from bright sunlight.
I'm interested in a good pair of winter flat light glasses too - it looks like Method 7 has completely changed their model names since 2019 and they have a lot of different choices. I'm also looking at flying eyes - they have a two yellow tinted options with arout 85% VLT that might be good choices? They magnetic clip on for their prescription frames which are really nifty except I doubt they'll make the clip ons with those tints.
https://flyingeyesoptics.com/our-lenses/
Looking at the YLW or AMB lenses there.
https://flyingeyesoptics.com/our-lenses/
Looking at the YLW or AMB lenses there.
BC12D-4-85
SPONSOR
Fairbanks, AK.
Many of us have obviously spent time in flat light. I'm not a skier but assume at their speed vision is critical. I have tried various lenses (for skiers, snowmachiners, and prescription) and settled for everyday use on brown photochromatic prescription lenses. Not the best however. If I were curious I'd source several and test in flat light. And not everyone sees the same world. Ask a dog.
Gary
Gary
NunavutPA-12
FRIEND
67.8N,115.1W CYCO Canada
As pointed out earlier, a very bright LED landing light, mounted as low as possible, is a big help in creating shadows so you will (might?) be able to see the drifts and the surface.
Nevertheless, we have enough dangers when flying in remote places during very cold weather. Enough that I choose not to do it anymore. And the dangers can be present not only when landing but also when in-flight in an area without much contrast on the ground. That horizon can disappear suddenly and without warning. Now you're IFR!
Often the best and safest option is to stay home.
Nevertheless, we have enough dangers when flying in remote places during very cold weather. Enough that I choose not to do it anymore. And the dangers can be present not only when landing but also when in-flight in an area without much contrast on the ground. That horizon can disappear suddenly and without warning. Now you're IFR!
Often the best and safest option is to stay home.
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courierguy
MEMBER
Inkom, Idaho
I carry "regular" sunglasses, plus some amber tinted ones when ski flying. It is common for me to switch them off back and forth, or not use any, several times during a flight, as there is no magic bullet for flat light. I'm a snowboarder, a 73 year old boarder, and I'm at the point that when it's a poor definition day I don't go, or if it turns that way after I'm on the mountain, I leave. Hitting bumps I can't see sucks, as does thinking I'm stopped but actually still moving, or the reverse. I've never snowmobiled, but I recently very quickly learned, after I started riding my electric snowbike, that decent viz is critical to that activity also. Getting whited out just isn't any fun it seems.
Couple paper lunch bags filled with small spruce branch clippingsÂ…. Throw out over LZ on inspection passÂ… gives some definition. Related: Couple Grapefruit size rocks to check ice thickness
Couple of tips I was given by an experienced fellaÂ….works great.
When younger and skiing those kind of lines you couldnÂ’t see down, IÂ’d always have that sack of clippings in my pack. Reach back, pull out a small handful, throw downhill in front of you, a turn or two and repeat until you get definition from rock couloir wall/ valley forest/etc.
Careful to the tenth power when very remote or deep cold. IÂ’ve gotten myself into unintended survival mode a couple few times. IÂ’m sure there will be moreÂ…
Couple of tips I was given by an experienced fellaÂ….works great.
When younger and skiing those kind of lines you couldnÂ’t see down, IÂ’d always have that sack of clippings in my pack. Reach back, pull out a small handful, throw downhill in front of you, a turn or two and repeat until you get definition from rock couloir wall/ valley forest/etc.
Careful to the tenth power when very remote or deep cold. IÂ’ve gotten myself into unintended survival mode a couple few times. IÂ’m sure there will be moreÂ…
BC12D-4-85
SPONSOR
Fairbanks, AK.
I carry some rolls of surveyor flagging tape. Color can vary but blue stands out best sometimes on white, red on vegetation, varies. Over open areas without terrain reference nearby throw some out and they'll unroll in the air and can mark a landing line on the snow, especially if there's any breeze. Note their alignment or movement if there's some wind on the surface. Before you leave stick a few tree branches in the snow with tape for next time.
Gary
Gary
akavidflyer
FRIEND
Soldotna AK
Flat light has many shades of grey. When on the snowmachine I have red, blue, amber and yellow tint lenses in the backpack and might switch several times throughout the day as the shade of flat changes on me. I have yellow tint glasses I use in the plane and they work pretty well for me, but one never knows the best "color" will be for the actual conditions unless you have them all and can switch up and see (no pun intended).
BC12D-4-85
SPONSOR
Fairbanks, AK.
We see more of these on road and all terrain vehicles every winter. They illuminate the road or ground ahead for better visibility. Some have colored LED's to offer even better contrast. I'd consider adding at least one to each gear leg or whatever low enough to improve vision on landing. I have something similar on my truck that helps see snow covered roads in real flat daylight.
https://extremeledlightbars.com/
Gary
https://extremeledlightbars.com/
Gary
mvivion
SPONSOR
Bozeman,MT
cubdriver2
FRIEND
upstate NY
BC12D-4-85
SPONSOR
Fairbanks, AK.
Those of us in Alaska already landed wait for the Cubs.
Gary
Gary
courierguy
MEMBER
Inkom, Idaho
I for some reason didn't expect flat light to be an issue when riding my new snowbike last winter, I found out pretty quick it could be, after launching off a cornice I didn't notice. I stay in the brush or trees when possible, near them in the skiplane, and avoid wide open areas like the plague. Using lights would be cheating, but I can see them being effective.
