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Hi all,

 

I started this battle a few months ago with one of the Anigrand's resins I accumulated over the years. Thankfully I stopped purchasing them some time ago: as much as they can be tempting subjects for my tastes, the building experience is always somewhat painful!

So let's start with the raw materials:

 

P_20190118_213713

 

P_20190118_223054

 

Not much in the way of references: the program was terminated before any metal was cut so there is only a mockup (with two iterations) as reference and much imagination.

https://en.wikipedia.org/wiki/North_American_XF-108_Rapier

Most of the material available is in this feature article and a similar one in Le Fana de l'Aviation n°527.

 

P_20190118_213413

 

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I have this one, amongst other Anigrand kits, in the stash but have yet to summon both courage and time to start a build. In fairness to Anigrand I believe their later kits have improved, and from the beginning their subject selection has been excellent - how else would one be able to complete the full "Century Series" in 1/72?

 

Looking forward to your progress on this!

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12 minutes ago, CT7567 said:

how else would one be able to complete the full "Century Series" in 1/72?

You are so right! No wonder the reason behind this build is just a Century Series collection for our annual club display. I already built the Republic XF-103 some years ago, so we are done with the real oddities!

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I am also a fan of Anigrand resins, but to 1:144 scale.  Perhaps the 1:144 kits might be easier to build because I have built a few and really like them.

 

Mike

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Hmmmm..... its great to see a Rapier in the build :). It could have been a stunner if it had survived the design and procurement process. Hopefully yours will top trump that! ;). She'd look fantastic in that Edwards scheme :)

 

Good luck!

 

Martin 

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1 hour ago, Whirly said:

Not much in the way of references: the program was terminated before any metal was cut so there is only a mockup (with two iterations) as reference and much imagination.

https://en.wikipedia.org/wiki/North_American_XF-108_Rapier

Most of the material available is in this feature article and a similar one in Le Fana de l'Aviation n°527.

 

Dennis R. Jenkins' book on Experimentals and Prototypes has four pages on the type. Its worth seekinng out - a great reference.

 

Martin

 

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The oddest thing about this kit is that the main landing gear attachment points are not aligned properly, with the result that the port main landing strut is mounted further forward than the starboard strut, as can clearly be seen in your photos. The only way to fix this issue is to completely rebuild the main gear wells. The F-108 had a complicated set of main landing gear, with the port main gear folding inward and forward and the starboard main gear folding inward and aft, but Anigrand got the locations of the angled portions of the wheel well wrong..

 

There's a good bit of info on the F-108 on the Secret Projects forum:

 

https://www.secretprojects.co.uk/threads/north-american-f-108-rapier.408/

Edited by Space Ranger
Eliminate reference to missile bay; correct "F-109" to "F-108."
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Great looking jet, there’s a lot of Vigilante about it.  Good luck with the build.

 

AW

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1 hour ago, Andwil said:

Great looking jet, there’s a lot of Vigilante about it.

I have always felt the same, and have also wondered if there was any "cross pollination" between the F-108 and A3J design teams.

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2 hours ago, Andwil said:

Great looking jet, there’s a lot of Vigilante about it.  Good luck with the build.

 

11 minutes ago, Space Ranger said:

I have always felt the same, and have also wondered if there was any "cross pollination" between the F-108 and A3J design teams.

A properly motivated researcher, given appropriate city directories for the time period, could probably track down the post-work watering hole most likely to attract the relevant NAA engineering talent.  

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9 hours ago, Space Ranger said:

The oddest thing about this kit is that the main landing gear attachment points are not aligned properly,

 

There's a good bit of info on the F-109 on the Secret Projects forum:

https://www.secretprojects.co.uk/threads/north-american-f-108-rapier.408/

Thanks from me also for this info about the landing gear.  I am going to dig out my 1:144 version to check if the same applies to my kit.

 

I am following your build with interest Whirly, as I plan to start my 1:144 version of the kit in the near future.

 

Mike

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14 hours ago, Space Ranger said:

The oddest thing about this kit is that the main landing gear attachment points are not aligned properly, with the result that the port main landing strut is mounted further forward than the starboard strut, as can clearly be seen in your photos. 

 

Yes, I know that and I initially ignored the problem for laziness but now that I'm near the panting stage I really can't live with it. Must find a cure for my AMS!

 

'but Anigrand also got the angular relationship between the missile bay and the wheel well wrong.'  Please let me understand better what you mean: is the missile bay also wrongly located?

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The cockpit is quite spartan but overall adequate. I think the seat capsules might have some relationships with the Italeri B-58.

 

P_20190120_155611

 

The front u/c well was really a joke so I grinded away the resin ceiling preparing for a rebuild with thin plasticard.

 

P_20190120_155621

 

The bomb bay had also its problems (another big air bubble) so I cut it straight away.

 

P_20190127_122201

 

Here we start with the air bubble treatment: heat strectched sprue to variable diameters and super glue.

 

P_20190127_124042

 

P_20190127_124407

 

See also the thick plasticard I super glued behind the main u/c attachment posts, so that I can drill deeper holes.

 

P_20190127_130331

 

I added also metal pins to the box-like fuselage to help alignment.

 

P_20190127_155343

 

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17 hours ago, Whirly said:

 

Yes, I know that and I initially ignored the problem for laziness but now that I'm near the panting stage I really can't live with it. Must find a cure for my AMS!

 

'but Anigrand also got the angular relationship between the missile bay and the wheel well wrong.'  Please let me understand better what you mean: is the missile bay also wrongly located?

The missile bay is in the correct location, as far as I have been able to determine. I was momentarily confusing it with the central, rectangular portion of the wheel wells. I apologize for the lack of clarity in my statement about the "angular relationship." I was referring to the angle between the outboard portion of the wheel wells (the portion housing the struts when retracted) and the central portion (the portion housing the wheels themselves) as observed on the underside of the airframe. That has to be the same for both wheel wells. You can't just relocate one landing gear mounting point to line up with the other without either (1) adjusting an entire angular portion fore or aft while maintaining the same angle, in which case one wheel well or the other is then mislocated with respect to the length of the central portion, or (2) the entire landing gear well area has to be ripped out and a new one designed and built. It's a mess.

 

If this explanation is not any clearer, I apologize for that as well. I will try to post a photo later showing what I mean. It took me a while to realize what the problem was, and it so discouraged me that I put the kit away years ago and had not even looked at it until this thread appeared.

Edited by Space Ranger
Eliminate reference to missile bay, clarify description of wheel wells.
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I always wanted to build the Anigrand F-108.

 

What I never seen is an size comparizon between the F-108 and the Vigilante, Avro Arrow and the B-58...

 

Following with interest!

 

Cheers / André

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The attached photo of the lower fuselage half of my kit illustrates the issues with the Anigrand F-108 kit's wheel wells. Note that the port landing gear mounting point is 5 mm further forward than the starboard landing gear mounting point (measurements were taken directly from the part instead of off the photo to eliminate any error caused by distortions in the latter). Now you would think that this problem could be solved simply by moving the starboard landing gear mounting point forward or the port landing gear mounting point aft by the difference of 5 mm. But it's not as simple as that, because dimension "a" must equal dimension "a´(a-prime)" and dimension "b" must equal dimension "b´(b-prime)" (ignore the black spot above a´; it's a speck of dust I failed to notice). Also, angle A must equal angle B. The only way to accomplish all of this is to "split the difference" and move the port landing gear mounting point aft a distance of 2.5 mm and the starboard landing gear mounting point forward by the same amount. But if that's all you do, you'll be drilling holes into the edges of the angled portions of the wheel well and vertically into the walls, an iffy proposition at best. The ideal solution is to move the entire angled portions of the wheel wells forward and aft as required, maintaining angles "A" and "B," but due to the corners where the angled portions meet the rectangular central portion, this is also going to be difficult. When/If I get around to building my kit, I'm going to grind away the entire wheel well interior structure, relocate the angled openings in the fuselage belly, and build a new wheel well interior to fit from scratch.

 

Anigrand Wheel Wells

 

Here's what is arguably the best scale drawing of the F-108. This is from the instruction/plan sheet for the KR Models vacform kit. This kit was designed, manufactured, and sold by Ken Rymal of Shelby, Ohio, some 40+ years ago, and probably builds up into a better model: The missile bay and wheel well callouts are my addition:

 

KR Models 2-View

 

And, finally, here is an inboard profile view from the same instruction sheet. Note how the main wheels wind up being stowed at both vertical and horizontal angles when retracted. This allowed a landing gear long enough for the rotation required for takeoff as well as a shock strut long enough to absorb landing loads, Such a landing gear retracting at the normal 90° would have required a wider fuselage, which would have meant extra structural weight, which would have required extra fuel, which would further increase loaded weight, which would have required a heavier landing gear, etc., etc. To allow the main gear to retract in this manner, the struts were designed with the trunnions at an angle to the aircraft's centerline (and the vertical plane of the wheels) instead of parallel to it. Little did the North American engineers realize the anguish their landing gear design would cause kit designers and model builders in future years. But it's still a great-looking aircraft, even if it never was built.

 

KR Models Profile View

 

I've eliminated all reference to the missile bay in earlier posts. I was momentarily mistaking the rectangular central portion of the wheel well for it, having not examined the kit in some time. The missile bay is the least of this kit's problems.

 

Edited by Space Ranger
Minor corrections.
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Interesting how Avro solved the problem with the landing gear on the Arrow by building the aircraft with angled wings...

 

Cheers / André

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3 minutes ago, Andre B said:

Interesting how Avro solved the problem with the landing gear on the Arrow by building the aircraft with angled wings...

 

Cheers / André

The Arrow's landing gear was not the primary reason for its delta wing; high-speed aerodynamics was the reason. But the Arrow's main landing gear worked similarly to that proposed for the F-108, in that it retracted at an angle to the fuselage. But because the Arrow's wing was so thin, its landing gear also had to twist on retraction so the wheels could lie flat. In a well-documented accident, one of the Arrow's main gear legs failed to twist, causing the airplane to skid off the runway on landing.

 

The landing gear of the C-5 Galaxy is perhaps the most complicated of any current aircraft. The main wheel bogies rotate 90° inward prior to retraction. Then, as the struts begin to retract, the fronts of the bogies drop and the bogies remain relatively level and ride on tracks into the fuselage as the struts complete the retraction cycle and the doors close. There are some YouTube videos showing this.


We're letting this thread drift, but if you're interested in landing gear design, a Japanese website has some great animations of various aircraft landing gears:

http://www5a.biglobe.ne.jp/~t_miyama/lgindx.html (The index to aircraft is on the lower left of the page.)

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17 minutes ago, Space Ranger said:

The Arrow's landing gear was not the primary reason for its delta wing...

 

Sorry, I wasn't precise. It was by building the Arrow with some anhedral of the wings (down angled) that made it possible to build it with shorter landing gear and solve some of the problems. It is one of the things mentioned  concerning the construction of the Avro Arrow.

 

Cheers / André

Edited by Andre B
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3 minutes ago, Andre B said:

 

Sorry, I wasn't precise. It was by building the Arrow with some anhedral of the wings (down angled) that made it possible to build it with shorter landing gear and silver some of the problems. It was one of the things mentioned during construction of the Avro Arrow.

 

Cheers / André

You're quite correct. I took your reference to "angled wings" to mean "delta wings." My apologies. There are a lot of "angles" to this discussion!

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