Welsh Air Display USAF style
Join Date: Jul 2001
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Evening all.
Sorry for keeping this thread going but i thought you may be interested in the following comments that i have had regarding the Eagle photo's.
These were sent to me in a presentation that someone had done and has been all around the Eagle community.
I have had several e mails from Boeing on the subject aslo, with one comment coming from an engineer last night.
Stunning is certainly the right word to use. The interesting part for me is the change in flow viz patterns on the upper wing as angle of attack changes. I've been working F-15 aerodynamics for 20+ years and have never seen such a clear representation of the airflow as your photos. Just from these four photos I've got a much better understanding of the flowfield around the jet.
These are the points made.
1. Condensation indicates regions of high velocity low pressure air flow.
2. F15 is at high sub sonic mac, but relatively low AOA.
( No flow separation on wing )
3. Tanks / missiles on wing pilons seem to have some influence on flow over wing. More pronounced on left hand wing for some reason?
4. Wing tips appear deflected up due to high load factor.
1. Higher AOA than photo no 1. ( regions of flow separation on wing starting to become visible)
2. Effect of wing tanks / missiles more noticeable.
3. No separation on outer wing panels ( lower local AOA due to conical wing twist.)
4. Small tight vortices emanating from inlet lips.
5. Vortex from left hand wing root extension barely visible.
6. Lack of vortex on right hand wing root extension. ( Effect of Gun Port? )
1. Similar characteristics as photo no 2.
1. Higher AOA than photo's 2 & 3. ( More flow separation visible on wing.)
2. Larger well defined vortices emanating from both inboard and outboard inlet lips.
Right hand outboard inlet lip vortex dissipated further forward than left hand vortex. ( Effect of Gun louver exhaust? )
3. Vortex emanating from left hand wing route extension weaker, less well defined than vortex from inlet lip.
Smooth, rounded OML as compared to sharp inlet lip.
4. Lack of vortex on right hand wing route extension ( Effect of Gun port? )
I do hope this is of interest to you and will let you know of any further developments.
Still not had a flight though !!
Hard enough job trying to get into a tanker to photograph them.
Cheers Ricko.
Sorry for keeping this thread going but i thought you may be interested in the following comments that i have had regarding the Eagle photo's.
These were sent to me in a presentation that someone had done and has been all around the Eagle community.
I have had several e mails from Boeing on the subject aslo, with one comment coming from an engineer last night.
Stunning is certainly the right word to use. The interesting part for me is the change in flow viz patterns on the upper wing as angle of attack changes. I've been working F-15 aerodynamics for 20+ years and have never seen such a clear representation of the airflow as your photos. Just from these four photos I've got a much better understanding of the flowfield around the jet.
These are the points made.
1. Condensation indicates regions of high velocity low pressure air flow.
2. F15 is at high sub sonic mac, but relatively low AOA.
( No flow separation on wing )
3. Tanks / missiles on wing pilons seem to have some influence on flow over wing. More pronounced on left hand wing for some reason?
4. Wing tips appear deflected up due to high load factor.
1. Higher AOA than photo no 1. ( regions of flow separation on wing starting to become visible)
2. Effect of wing tanks / missiles more noticeable.
3. No separation on outer wing panels ( lower local AOA due to conical wing twist.)
4. Small tight vortices emanating from inlet lips.
5. Vortex from left hand wing root extension barely visible.
6. Lack of vortex on right hand wing root extension. ( Effect of Gun Port? )
1. Similar characteristics as photo no 2.
1. Higher AOA than photo's 2 & 3. ( More flow separation visible on wing.)
2. Larger well defined vortices emanating from both inboard and outboard inlet lips.
Right hand outboard inlet lip vortex dissipated further forward than left hand vortex. ( Effect of Gun louver exhaust? )
3. Vortex emanating from left hand wing route extension weaker, less well defined than vortex from inlet lip.
Smooth, rounded OML as compared to sharp inlet lip.
4. Lack of vortex on right hand wing route extension ( Effect of Gun port? )
I do hope this is of interest to you and will let you know of any further developments.
Still not had a flight though !!
Hard enough job trying to get into a tanker to photograph them.
Cheers Ricko.
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Ricko, aircraft dynamics isn't my thing, so I could be way off here but re #1
Could be due to the AMRAAM on that side vs the winder and pod on the other?
sw
3. Tanks / missiles on wing pilons seem to have some influence on flow over wing. More pronounced on left hand wing for some reason?
sw
Join Date: Jul 2006
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Interesting on the Hornets... the lighting highlights are different on the 2 #7s, as is the fading of the paint... could be they had just got one back from repair and the home crew had painted it with the wrong number (should have been #6 I believe)?
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RICKO, Awasome shots
, I'm also a photog (20D + grip + 70-2002.8 IS) in what spare time I have. I have to say that your shots are poss the best I have ever seen. Clean, un-clutterred and pin sharp with outstanding panning. I would be very proud of them If I were you.Looks like I need to plan a trip to Wales myself, any tips on the best vantage points most welcome (have also had a look at lowfly.net).
Keep up the work, and as the rest say any more pics to show!!
Join Date: Jul 2001
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Afternoon.
Spannermonkey.
I'll send you a pm.
Polikarpov.
I know they are aware of the GLOBAL interest but not too sure if they have seen this thread on hear.I will pass on a link as it would be good to get some feedback from the 'inside' so to speak.
Ricko.
Spannermonkey.
I'll send you a pm.
Polikarpov.
I know they are aware of the GLOBAL interest but not too sure if they have seen this thread on hear.I will pass on a link as it would be good to get some feedback from the 'inside' so to speak.
Ricko.
Join Date: Jul 2001
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Many thanks for all the comments about the Eagle shots.
May i take this opportunity to wish you all a very Merry Christmas and a Happy New Year.
To all of you who are away over the festive season , GOD BLESS and be safe.
Regards Richard.
May i take this opportunity to wish you all a very Merry Christmas and a Happy New Year.
To all of you who are away over the festive season , GOD BLESS and be safe.
Regards Richard.
