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Author Topic: ADF to LWF: Evolution of the General Dynamics F-16  (Read 54656 times)

Offline kaiserd

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Offline r16

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #91 on: January 06, 2017, 01:44:27 am »
such a mouthful name "Advanced Fighter Aircraft Study Avenging Falcons" , almost Soviet and telling how they will take revenge for their heroic fliers ... Is it avenging the fallen , or the Falcons will be avenging ?  And yes , the PDF is really neat .

Offline Arjen

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #92 on: January 06, 2017, 01:56:35 am »
Like.

Offline hesham

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #93 on: May 26, 2017, 05:02:18 am »
From air Enthusiast.

Offline ScrutorAudax

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #94 on: October 02, 2017, 07:54:14 am »
I don't know if this has been posted here before, but I found this report.

https://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/19790019972.pdf

Edit: It has been, sorry.
« Last Edit: October 10, 2017, 11:03:08 am by ScrutorAudax »

Offline ScrutorAudax

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #95 on: November 13, 2017, 04:15:44 pm »
Is there any information about the development of the F-16's ventral fins?

Offline PaulMM (Overscan)

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #96 on: November 13, 2017, 04:58:18 pm »
A good question, to which I don't have an answer (yet). They are primarily for directional stability at supersonic speed, I believe.
« Last Edit: November 13, 2017, 05:33:36 pm by PaulMM (Overscan) »
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Offline ScrutorAudax

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #97 on: November 13, 2017, 06:07:39 pm »
My question primarily regards their placement, shape, size and number.  They are clearly shaped for low supersonic drag near bi-convex airfoil, and for clearance at takeoff (shorter at the rear), but I am curious if they studied single fins or placement similar to the na-335.

Offline AeroFranz

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #98 on: November 13, 2017, 07:30:05 pm »
single fin might have been taller for a given area, not good for tailstrike (as you mentioned)
All modern aircraft have four dimensions: span, length, height and politics.   TSR.2 got the first three right - Sir Sydney Camm

Offline PaulMM (Overscan)

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #99 on: November 13, 2017, 09:28:54 pm »
Good general discussion on ventral fins: http://www.f-16.net/forum/viewtopic.php?f=38&t=52649
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Offline PaulMM (Overscan)

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #100 on: November 13, 2017, 09:44:30 pm »
Most of the early F-16 designs have 2 long and shallow ventral fins of a traditional type (like General Dynamic's F-111). These are going to be lighter weight for the same stability factor as a single folding large fin of higher aspect ratio (for structural reasons).

The final ventral fins are more forward located and taller, a higher aspect ratio. It arrived with a design iteration intended to improve area ruling to reduce drag at Mach 1.2, but I can't say if that is coincidence or not.

Regarding the NA-335, and F8U-3, both were Mach 2.3+ designs, it's possible they needed bigger ventral surfaces for supersonic stability and accepted more weight. Neither was in a competition for a lightweight fighter...
« Last Edit: November 13, 2017, 09:49:54 pm by PaulMM (Overscan) »
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Offline ScrutorAudax

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #101 on: November 14, 2017, 11:46:39 am »
I with the NA-335 I was thinking of the placement only, not the size.  Upon further consideration, the JF-17 is a better example.

Offline PaulMM (Overscan)

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #102 on: November 14, 2017, 11:23:06 pm »
I with the NA-335 I was thinking of the placement only, not the size.  Upon further consideration, the JF-17 is a better example.

My guess - JF-17 placement follows Lavi/J-10 ventral fin positioning (low wing designs) with its mid-low wing position.  The JF-17 aft strake is significantly lower relative to the fuselage compared to the F-16, so the ventral fins are in a better position than they would be on an F-16. The F-16 ventral fins are mounted on the fuselage taking them into undisturbed air.
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Offline Mark Nankivil

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #103 on: November 21, 2017, 08:41:06 am »
Good Day All -

Though not about the F-16, Jack Abercrombie's story of the evolution of the F-15 vertical fins illustrates the various factors that need to be addressed by the vertical fin area and how it is distributed/sized:

https://www.docdroid.net/U9S6z45/f-15-eagle-prelude-to-flight-a-tall-tail-tale.pdf

Enjoy the Day!  Mark

Offline AeroFranz

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Re: ADF to LWF: Evolution of the General Dynamics F-16
« Reply #104 on: November 21, 2017, 11:35:25 am »
Good read. thanks, Mark!
All modern aircraft have four dimensions: span, length, height and politics.   TSR.2 got the first three right - Sir Sydney Camm