If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below. |
|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
Yesterday, I was flying along the tops of a broken layer and picked up
a thin layer of frost/ice on the wings with a thin triangle-shaped pattern to the frost. This was a new one to me. Conditions: Plane: Cherokee 180 Altimeter 30.05 Broken layer @ 4000MSL (~3000AGL) OAT = -5degF Clear above the 040 BKN layer Time was 10am, which put the sun almost directly behind the plane. The leading edge of the wing was clear (free of frost) from the leading edge to approximately 8 inches back (chordwise). At the 8-inch chord mark, several frost outlines in a triangle shape were present. The frost outline started as a point, and tapered back evenly on either side, slowly 'enlarging' the frost pattern so that it looked like a triangle pointed towards the leading edge. There were several of these patterns on the wing, one every few feet (spanwise). The frost patterns were not aligned with the rivets. The frost triangles were about 1-2 feet long and 6 inches wide. The OAT gauge/windshield did not accumulate any frost/ice. Explanations? Similar occurrences? -Nathan |
#2
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
It is probably due to structure on your airplane being colder than the air.
The triangles are probably reinforcements or doublers under the skin. I get this a lot on the MU-2 after landing when the fuel is at -40C and frost forms on the underside of the wing where the fuel contacts the skin. Mike MU-2 "Nathan Young" wrote in message news Yesterday, I was flying along the tops of a broken layer and picked up a thin layer of frost/ice on the wings with a thin triangle-shaped pattern to the frost. This was a new one to me. Conditions: Plane: Cherokee 180 Altimeter 30.05 Broken layer @ 4000MSL (~3000AGL) OAT = -5degF Clear above the 040 BKN layer Time was 10am, which put the sun almost directly behind the plane. The leading edge of the wing was clear (free of frost) from the leading edge to approximately 8 inches back (chordwise). At the 8-inch chord mark, several frost outlines in a triangle shape were present. The frost outline started as a point, and tapered back evenly on either side, slowly 'enlarging' the frost pattern so that it looked like a triangle pointed towards the leading edge. There were several of these patterns on the wing, one every few feet (spanwise). The frost patterns were not aligned with the rivets. The frost triangles were about 1-2 feet long and 6 inches wide. The OAT gauge/windshield did not accumulate any frost/ice. Explanations? Similar occurrences? -Nathan |
#3
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
On 2005-12-06, Mike Rapoport wrote:
this a lot on the MU-2 after landing when the fuel is at -40C and frost forms on the underside of the wing where the fuel contacts the skin. What, Prist can't fix that?! ;-) -- Ben Jackson http://www.ben.com/ |
#4
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
An advertisement for Sci-Fi Channel's new mini-series?
|
#5
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
On 07 Dec 2005 00:36:05 GMT, Blanche wrote:
An advertisement for Sci-Fi Channel's new mini-series? Well, this did happen in the Minneapolis area, so perhaps it had something to do with the light pillars mentioned a day ago. :-) |
#6
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
In article ,
Nathan Young wrote: On 07 Dec 2005 00:36:05 GMT, Blanche wrote: An advertisement for Sci-Fi Channel's new mini-series? Well, this did happen in the Minneapolis area, so perhaps it had something to do with the light pillars mentioned a day ago. :-) I could throw in some more than usually uninformed speculation (even for this group . . . ) about a random dot of frost forming, causing the airflow to spread out laterally just a bit; gases cool when they expand (happens in nozzles and many types of refrigerators); result is more frost forming in the region just behind the dot; and the forward-pointing triangle grows toward the rear of the plane. Fits the available data presented thus far, and stranger things happen in gas and liquid flows all the time -- but I have no idea if anything like this is really happening here. |
#7
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
"AES" wrote in message
... I could throw in some more than usually uninformed speculation (even for this group . . . ) about a random dot of frost forming, causing the airflow to spread out laterally just a bit [...] That was the theory I came up with too. That should be enough to cause you concern for whether you're actually correct. (I didn't post it, because it seemed too outlandish, even for me ). |
#8
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
"AES" wrote in message ... In article , Nathan Young wrote: On 07 Dec 2005 00:36:05 GMT, Blanche wrote: An advertisement for Sci-Fi Channel's new mini-series? Well, this did happen in the Minneapolis area, so perhaps it had something to do with the light pillars mentioned a day ago. :-) I could throw in some more than usually uninformed speculation (even for this group . . . ) about a random dot of frost forming, causing the airflow to spread out laterally just a bit; gases cool when they expand (happens in nozzles and many types of refrigerators); result is more frost forming in the region just behind the dot; and the forward-pointing triangle grows toward the rear of the plane. Fits the available data presented thus far, and stranger things happen in gas and liquid flows all the time -- but I have no idea if anything like this is really happening here. Yes, maybe that is the area where the boundary layer was breaking from laminar flow to turbulent flow. It may be a new way to figure out where to place the vortex generators... |
#9
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
On Tue, 06 Dec 2005 15:52:16 GMT, "Mike Rapoport"
wrote: It is probably due to structure on your airplane being colder than the air. The triangles are probably reinforcements or doublers under the skin. I will have to ask my A&P. I am fairly certain that on a Cherokee, the inner wing is much simpler than that... Ie ribs with the outer wing skin riveted to them. |
#10
|
|||
|
|||
Triangle shaped ice/frost on the wing - anyone seen this?
On Tue, 06 Dec 2005 21:16:17 -0800, AES wrote:
In article , Nathan Young wrote: On 07 Dec 2005 00:36:05 GMT, Blanche wrote: An advertisement for Sci-Fi Channel's new mini-series? Well, this did happen in the Minneapolis area, so perhaps it had something to do with the light pillars mentioned a day ago. :-) I could throw in some more than usually uninformed speculation (even for this group . . . ) about a random dot of frost forming, causing the airflow to spread out laterally just a bit; gases cool when they expand (happens in nozzles and many types of refrigerators); result is more frost forming in the region just behind the dot; and the forward-pointing triangle grows toward the rear of the plane. Fits the available data presented thus far, and stranger things happen in gas and liquid flows all the time -- but I have no idea if anything like this is really happening here. This was my best guess as well. I wish had my digital camera with me - would have been a good one to capture. |
Thread Tools | |
Display Modes | |
|
|
Similar Threads | ||||
Thread | Thread Starter | Forum | Replies | Last Post |
terminology questions: turtledeck? cantilever wing? | Ric | Home Built | 2 | September 13th 05 09:39 PM |
Nearly had my life terminated today | Michelle P | Piloting | 11 | September 3rd 05 02:37 AM |
Grob G102 Setup | BDS | Soaring | 11 | August 30th 05 03:42 PM |
Props and Wing Warping... was soaring vs. flaping | Wright1902Glider | Home Built | 0 | September 29th 03 03:40 PM |
An Affordable Homebrue 60 in DS machine | Grant | Soaring | 0 | August 8th 03 03:52 AM |