eugegall
Topic Author
Posts: 64
Joined: Sun Dec 27, 2009 9:13 pm

Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 8:42 pm

Hi All,

I was flying Virgin Atlantic G-VTOP (unfortunately) from Las Vegas to Gatwick on November 3rd.

I've flown lots of times but have never noticed a build up of ice on the engine before. I guess this is quite common and probably down to the time of year and atmospheric conditions.

Is it common?

Happy new year!!

http://i22.photobucket.com/albums/b315/eugeclio172/IMG_2062_zpsce19959d.jpg

[Edited 2012-12-31 12:43:21]
 
User avatar
zeke
Posts: 9855
Joined: Thu Dec 14, 2006 1:42 pm

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 8:44 pm

I cannot see any in that photo, are you able to zoom into the areas you think have ice and repost them ?
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
eugegall
Topic Author
Posts: 64
Joined: Sun Dec 27, 2009 9:13 pm

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 8:49 pm

Its on the closest engine right at the front/bottom. I know it was ice as I watched it progressively melt as we descended.
 
MesaFlyGuy
Posts: 3819
Joined: Fri Dec 21, 2012 8:36 pm

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 8:56 pm

I see the ice (I think I do) on the close engine. It can reach upwards of -60 degrees farenheit at that altitude, so it is likely that any condensation would instantly melt. As the aircraft started to descend, the temperature would rise, causing the ice to melt,cwhich is what you observed.
The views I express are my own and do not reflect the views and opinions of my company.
 
N243NW
Posts: 1597
Joined: Thu Jul 24, 2003 4:29 am

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 8:57 pm

It looks to me that it may have just been the absence of a shadow on that part of the engine that makes it look like icing. Perhaps as you descended the angle of the sun gradually changed and that was what caused the apparent ice to disappear...?

Unless you were cruising inside clouds (with visible moisture around the aircraft), it seems somewhat unlikely that ice would build up in this fashion. I'd be happy to be proven wrong, though.
B-52s don't take off. They scare the ground away.
 
User avatar
zeke
Posts: 9855
Joined: Thu Dec 14, 2006 1:42 pm

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 8:58 pm

The lighter area is just sunlight, the fuselage is blocking the sun, the round shadow is on the wing.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
eugegall
Topic Author
Posts: 64
Joined: Sun Dec 27, 2009 9:13 pm

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 9:04 pm

Here is another image. Circled in Red.

I'm 99% sure its ice and not shadow or condensation.

http://i22.photobucket.com/albums/b315/eugeclio172/IMG_2063_zps2900a933.png
 
CosmicCruiser
Posts: 2049
Joined: Tue Feb 22, 2005 3:01 am

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 9:35 pm

I think it's sunlight and not ice at all. doesn't look like the way ice would form anyway. naw.
 
eugegall
Topic Author
Posts: 64
Joined: Sun Dec 27, 2009 9:13 pm

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 9:43 pm

All due respect you can see from the last picture that the engine in question is in shadow meaning it cant be sunlight.
 
Gatorman96
Posts: 807
Joined: Wed Dec 07, 2005 2:22 am

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 10:26 pm

Quoting eugegall (Reply 8):

All due respect you can see from the last picture that the engine in question is in shadow meaning it cant be sunlight.

Fair enough, but you have multiple respected members in this thread (pilots I might add), all in agreement that this is not ice.

I have flown thousands of hours as a passenger myself and have never noticed ice buildup on the nacelle like this either.
Cha brro
 
CosmicCruiser
Posts: 2049
Joined: Tue Feb 22, 2005 3:01 am

RE: Engine Icing Mid Flight (Atlantic)

Mon Dec 31, 2012 10:39 pm

It appears that though most of the engine is in shadow there is still a little light hitting that lower nacelle.
 
XFSUgimpLB41X
Posts: 3960
Joined: Fri Aug 25, 2000 1:18 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 12:00 am

Looks like a glint of light to me. Doesn't look like ice...
Chicks dig winglets.
 
futureualpilot
Posts: 2404
Joined: Thu May 25, 2000 10:52 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 12:36 am

That looks a lot more like sunlight coming under the fuselage than ice to me. It would be very odd to have only a small strip of ice like that form in one particular spot at altitude in clear air.
Life is better when you surf.
 
Mir
Posts: 19093
Joined: Mon Jan 05, 2004 3:55 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 12:39 am

Quoting eugegall (Reply 2):
I know it was ice as I watched it progressively melt as we descended.

Which was almost definitely the shadow moving as a result of the change in position of the sun relative to the aircraft.

-Mir
7 billion, one nation, imagination...it's a beautiful day
 
Okie
Posts: 3553
Joined: Wed Jul 16, 2003 11:30 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 12:41 am

Looks like reflected light from the clouds from my observation, possibly reflected from the fuselage but the angle does not look correct for that.

It is just too dry and too cold for ice to form on the nacelle at that altitude as previously indicated.

Okie
 
eugegall
Topic Author
Posts: 64
Joined: Sun Dec 27, 2009 9:13 pm

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 12:49 am

That is exactly my point for posting this. I thought it was very, very odd to see.

Guys of course I could be wrong and obviously I am in the minority in thinking its ice or frozen condensation but I too have a pilots licence. Yes its only a PPL but I do have a very good basic knowledge of the main principles of flight.

I watched it form and I watched it dissolve. It did not change shape through aircraft turns which is why I am sticking to my guns and stating its not light. Even the pictures back my story up. The light glare/shade/shadow on the outside engine is completely difference place to the inside engine. IF it was light the shapes on both engines would be in the same place, or at least very close. On the images the light on the outside engine is on the far right hand side. On the inside engine the light is on the very bottom. Unless there is a second sun that I am unaware of I guess its not light causing that.
 
CosmicCruiser
Posts: 2049
Joined: Tue Feb 22, 2005 3:01 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 2:33 am

man if you saw all the weird shadows and light combos that can happen you would be surprised. light can be in all sorts of weird places and that can create some awesome sights but ice no. Ice forming that much should be around the whole inlet and as someone said it's probably too cold anyway.
 
User avatar
zeke
Posts: 9855
Joined: Thu Dec 14, 2006 1:42 pm

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 12:06 pm

Quoting eugegall (Reply 15):

What you are seeing is the shadow of the front of the fuselage with the sun relatively low and to the right of the aircraft. The give away is how well the light reaches the fan and under side of the pylon of #1. If the sun was higher, the rear of teh inlet and the pylon of #1 would have a shadow.
We are addicted to our thoughts. We cannot change anything if we cannot change our thinking – Santosh Kalwar
 
26point2
Posts: 814
Joined: Wed Mar 03, 2010 6:01 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 2:24 pm

Yes. Clearly flying toward the sunrise. Shadow on the wing looks like the front of the plane/hump and with a bit of shadow on engine 1 one can imagine the shape of the rest of the nose within the shadow.

Any inflight structural ice would accumulate evenly on the entire engine inlet...all the inlets as amateur of fact.

Structural ice can form at these altitudes under unusual conditions but is rare. The GLEX has reports of inflight engine TAT probe icing causing engine rollback. Didn't the AF crash over the Pacific encounter probe ice before they lost control?
 
CaptCufflinks
Posts: 95
Joined: Thu Dec 06, 2012 10:24 am

RE: Engine Icing Mid Flight (Atlantic)

Tue Jan 01, 2013 10:25 pm

It's got to be an optical illusion, rather than ice - in fact, if you take a look at this picture (same aircraft) you'll notice that the outboard engine has an identical look to it. It's a tiny bit brighter in this image, so you can see the same "shiny" effect on other parts of the engine.

http://www.airliners.net/photo/Virgi...d=43386e71abcd2b7ccdde9575c95ea559

[Edited 2013-01-01 14:27:16]
 
User avatar
akiss20
Posts: 771
Joined: Tue Sep 04, 2007 9:50 am

RE: Engine Icing Mid Flight (Atlantic)

Wed Jan 02, 2013 1:43 am

Engine's are required to go through very stringent icing tests to pass certification. Icing tests are one of the most difficult tests they must pass as they represent icing conditions almost NEVER seen (engine manufacturers are always arguing with the FAA as to whether the tests should be as stringent as they are).

This past summer I worked with GE on some ice accretion modelling as well as reviewing videos of icing tests to better ice shedding models. I can't show any of the images as it is all highly proprietary, but there were some tests where I was damn amazed that the engine could keep going. Thing looked practically like a block of ice.
Change will not come if we wait for some other person or some other time. We are the ones we've been waiting for. We are
 
ymincrement
Posts: 25
Joined: Thu Jul 05, 2012 3:33 pm

RE: Engine Icing Mid Flight (Atlantic)

Wed Jan 02, 2013 7:29 pm

Are these new engines safe in bad weather conditions? Heavy rain or snow could affect them?
 
User avatar
BreninTW
Posts: 1543
Joined: Sun Jul 02, 2006 5:31 pm

RE: Engine Icing Mid Flight (Atlantic)

Thu Jan 03, 2013 1:05 am

Quoting ymincrement (Reply 21):
Are these new engines safe in bad weather conditions? Heavy rain or snow could affect them?

They are very thoroughly tested for water and ice ingestion, as can be seen in the following two videos:

1) Hail ingestion test (750 kg of ice in 30 seconds)
http://www.youtube.com/watch?v=RafoUW3XfSk

2) All the tests (Hail as above, water 4,500 kg per minute)
http://www.youtube.com/watch?v=5xlObdXF8VE
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: Engine Icing Mid Flight (Atlantic)

Thu Jan 03, 2013 3:21 am

Quoting ymincrement (Reply 21):
Are these new engines safe in bad weather conditions?

Yes.

Quoting ymincrement (Reply 21):
Heavy rain or snow could affect them?

If it's sufficiently high, yes. However, weather conditions necessary to generate enough rain/snow are so severe that you should never be operating an airplane in them in the first place. Taca Flight 110 is the cannonical case for preciptation leading to an engine shutdown: http://en.wikipedia.org/wiki/TACA_Flight_110

Both the engine OEM and the airframer test for water and icing ingestion and those tests are *far* more severe than anything observed in what's supposed to be normal operation.

Tom.
 
User avatar
Aaron747
Posts: 8545
Joined: Thu Aug 07, 2003 2:07 am

RE: Engine Icing Mid Flight (Atlantic)

Fri Jan 04, 2013 5:25 am

I would respectfully second the others' comments that this is indeed an optical illusion. It is simply inconceivable that ice would accumulate in that particular location only.

Quoting ymincrement (Reply 21):
Are these new engines safe in bad weather conditions?

You bet they are. If I can be picky though, the GE CF6s pictured above have been mounted to various wings since the late 1980s  
If you need someone to blame / throw a rock in the air / you'll hit someone guilty
 
tdscanuck
Posts: 8572
Joined: Wed Jan 11, 2006 7:25 am

RE: Engine Icing Mid Flight (Atlantic)

Fri Jan 04, 2013 3:02 pm

Quoting Aaron747 (Reply 24):
It is simply inconceivable that ice would accumulate in that particular location only.

Although I agree it's most likely a lighting effect in this particular case, it's not inconceivable to have ice only in that particular location...for many nacelle anti-ice systems, the piccolo tubes that distribute hot air inside the nacelle leading edge are shaped like a "C" with the opening pointed down (air comes in at the top in the "middle" of the C and exits small holes all along the C). As a result, if you had a marginal/failing anti-ice valve that wasn't providing full flow, the first part of the nacelle that would get cold and start to ice (assuming icing conditions were present) is the bottom center.

Tom.
 
User avatar
CALTECH
Posts: 2774
Joined: Thu May 17, 2007 4:21 am

RE: Engine Icing Mid Flight (Atlantic)

Sat Jan 05, 2013 3:24 pm

Quoting eugegall (Reply 6):
I'm 99% sure its ice and not shadow or condensation.

  

Quoting zeke (Reply 5):
The lighter area is just sunlight, the fuselage is blocking the sun, the round shadow is on the wing.

  

Quoting zeke (Reply 17):
What you are seeing is the shadow of the front of the fuselage with the sun relatively low and to the right of the aircraft. The give away is how well the light reaches the fan and under side of the pylon of #1. If the sun was higher, the rear of teh inlet and the pylon of #1 would have a shadow.

  

Not ice, just some sunshine. Pretty clear air there at cruise altitude, typical for the mid-Atlantic. Not a lot of moisture there.


Quoting tdscanuck (Reply 25):
Although I agree it's most likely a lighting effect in this particular case, it's not inconceivable to have ice only in that particular location...for many nacelle anti-ice systems, the piccolo tubes that distribute hot air inside the nacelle leading edge are shaped like a "C" with the opening pointed down (air comes in at the top in the "middle" of the C and exits small holes all along the C). As a result, if you had a marginal/failing anti-ice valve that wasn't providing full flow, the first part of the nacelle that would get cold and start to ice (assuming icing conditions were present) is the bottom center.

Not on any of our engine inlets. On all of our GE, Pratts and Rolls engines, the anti-ice spray tube is a "O" shaped tube. No "C" shape, and the tube is a complete circle. The hot air enters from the left side of the nacelle or looking at the fan face, at about the 2 - 3 o'clock position, and exits through a tap off the spray tube that blows overboard at or very near the bottom of the inlet.

Looking at your photos provided, the engine anti ice would have been selected off with that clear air at altitude, and any build up of ice on just that one engine inlet would have been much more uniform around the entire inlet, not just at that bottom area. The number 1 outboard engine would have had some ice build up as well. Just some sunshine and shadows making a optical illusion.
UNITED Would Be Nice

Who is online

Users browsing this forum: No registered users and 12 guests