Aluminum Honeycomb

[6R07mi]

During a discussion with a material engineer at work,
(we're a class 6~8 truck axle manufacturer formerly Rockwell, so "car" stuff doesn't often surface !)

he pulled out of a drawer a sample block of "laminated aluminum" panel,
as I've never handled a sample of the material, took photos and thought I'd share.

regards
jim p

[98SVT - was 06GT]

Yes - it's interesting stuff. Very experimental when the J Car crashed. Lots of different methods to fasten have been developed over the years. https://apps.dtic.mil/sti/pdfs/ADA305407.pdf  A friend built the BD-10 Jet prototypes in Nevada using this material. After the crash of the first Fox prototype they had another aeronautical engineer look at it https://biography.omicsonline.org/united-states-of-america/aerion-corporation/dr-richard-tracy-239318 On PJ-2 they changed the angle of the tails a couple degrees to reduce the stress and crossflow problems and that fixed it (they had done several test flights on the fix) . There had been comments that the honeycomb wasn't strong enough to handle the stress - due to the wrinkles on the first plane. It was a design problem not a material or build problem. My friend oversaw these builds too https://en.wikipedia.org/wiki/LearAvia_Lear_Fan They were done with newer composites that testing showed would handle the stress but .gov wanted more "proof".
On the J chassis they added a steel roll cage and more mechanical fasteners. The original had been mainly epoxied together which at the time was a very delicate process requiring exact pressures and temps - almost lab conditions. I'm pretty sure the J car used all flat panels. Now you can even have curved panels made but it has mostly fallen to the wayside with the carbon composites being much cheaper to build stronger complex shapes with.

[tesgt350]

I can't remember which Car Company but one was using that stuff for their Chassis because it made very easy to adjust the same Chassis to fit other Models unlike standard Unibody or Full Frame Vehicles.  I want to say it was Ford who did it first.

[Royce Peterson]

It's been used on production aircraft since around 1958. Maybe it's revolutionary for use in a car but bonded honeycomb sheet has been around forever.

[gt350bp]

Honeycomb building panels have been used for building facades since the 1960's or possibly the late 1950's. HH Robertson made honeycomb panels that would fit into curtainwall and storefront framing systems.

Don
gt350bp

[JohnSlack]

Yes - it's interesting stuff. Very experimental when the J Car crashed. Lots of different methods to fasten have been developed over the years. https://apps.dtic.mil/sti/pdfs/ADA305407.pdf  A friend built the BD-10 Jet prototypes in Nevada using this material. After the crash of the first Fox prototype they had another aeronautical engineer look at it https://biography.omicsonline.org/united-states-of-america/aerion-corporation/dr-richard-tracy-239318 On PJ-2 they changed the angle of the tails a couple degrees to reduce the stress and crossflow problems and that fixed it (they had done several test flights on the fix) . There had been comments that the honeycomb wasn't strong enough to handle the stress - due to the wrinkles on the first plane. It was a design problem not a material or build problem. My friend oversaw these builds too https://en.wikipedia.org/wiki/LearAvia_Lear_Fan They were done with newer composites that testing showed would handle the stress but .gov wanted more "proof".
On the J chassis they added a steel roll cage and more mechanical fasteners. The original had been mainly epoxied together which at the time was a very delicate process requiring exact pressures and temps - almost lab conditions. I'm pretty sure the J car used all flat panels. Now you can even have curved panels made but it has mostly fallen to the wayside with the carbon composites being much cheaper to build stronger complex shapes with.

I grew up knowing Dr. Richard Tracy, he was part of the engineering staff on our World Record holding raceplane Rare Bear. Among many other items he designed and built the wingtips on the clipped wings.


John

[98SVT - was 06GT]

I grew up knowing Dr. Richard Tracy, he was part of the engineering staff on our World Record holding raceplane Rare Bear. Among many other items he designed and built the wingtips on the clipped wings.

Being based at Stead was perfect for his love of fast planes. I think Rare Bear still holds a couple records. I haven't seen he and Ursula in years. Last time I saw him he was working on hypersonic stuff for .gov. Very talented, I'm sure his little composite Formula plane would have been competitive but he couldn't get any high angle CA joints to run the rear prop.

[Royce Peterson]

Honeycomb building panels have been used for building facades since the 1960's or possibly the late 1950's. HH Robertson made honeycomb panels that would fit into curtainwall and storefront framing systems.

Don
gt350bp

Both the Gulfstream GI and the Lockheed Jetstar flew around 1958 for the first time. Both used honeycomb bonded floor panels. I believe aluminum honeycomb was first used for floor panels in the Boing 707 that first flew around 1955. If there was any earlier use of it I am unaware.

[JohnSlack]

I grew up knowing Dr. Richard Tracy, he was part of the engineering staff on our World Record holding raceplane Rare Bear. Among many other items he designed and built the wingtips on the clipped wings.

Being based at Stead was perfect for his love of fast planes. I think Rare Bear still holds a couple records. I haven't seen he and Ursula in years. Last time I saw him he was working on hypersonic stuff for .gov. Very talented, I'm sure his little composite Formula plane would have been competitive but he couldn't get any high angle CA joints to run the rear prop.

The NAA has since changed the sporting rules allowing among other things GPS verification of the record runs. This makes the record runs much easier to verify for speed in a straight line, for example the 3Km record (1.864 mile) at the time August of 1989 my Dad had to fly the airplane with a 1Km entry area go through the 3Km course, exit the 3Km course without breaking out of the 1Km distance on the other end turn the airplane around without gaining more than 500' altitude, re-enter the 3Km section continue through to the other side of the course in the opposite direction once again turn around without gaining more than 500' altitude until 4 consecutive passes were made. The speeds on these passes were verified by flying over a narrow window that equated to synchronized cameras that were timing devices that had to have the film developed before the record could be confirmed. During the record runs the altitude through the 3Km course could not vary more than 300' from entry to exit of the 3Km section of the course. So back then if you went fast enough, but couldn't get through the narrow "frame" of the camera it didn't matter the record runs could not be confirmed. My Dad said that it was the hardest flying he had ever done. Due to the rule changes his record was retired, in addition to the 3Km record his time to climb record was retired as well from a standing start to 10,000 feet in 91.9 seconds.

The weight classes were changed as well a couple of years ago Steve Hinton in Voodoo exceeded the speed that my Dad had set in 1989 by the new rules. However if it were apples to apples he would not have the record because he did not exceed the required 1% increase in the speed. I am very happy for Stevo as he is a good friend and I designed the brackets for changing the wing angle for them. So technically Rare Bear holds the retired record under the old rules, while Stevo and Voodoo hold the record under the new rules.

It's all about going fast in an unlimited machine.


John

[SFM5S000]

My association and experience with Aluminum Honeycomb came in the way of competition alpine skis back in the mid 1970's.
I raced for a ski team at Squaw Valley's academy back then.
The company that built these skis is/was the HEXCEL Corporation, back then the emphasis was lightness. Aluminum Honeycomb was used as the core in place of wood cores for skis. They were extremely light weight. Their ads indicated they were from the aerospace industry, they were known for building helicopter blades. HEXCEL was based at one time in northern  California (Dublin). The skis were well received as a race ski but required special instructions for mounting Bindings (the mechanism that attaches ski boots, (for those who are unfamiliar with the sport)).
Attaching a binding required sticking a special tool to knock out a small area of honeycomb then filled with epoxy so the screws had material to hold on to.
They fell out of popularity because of the propensity for the bindings to rip out of the skis under competitive ski events.
I could imagine the Ford J cars had a special method for attaching the tubs.
Anyway, that's my experience/knowledge with aluminum honeycomb.
I believe the HEXCEL company still exists somewhere on the east coast.

Cheers
~Earl J

[JD]

Have a client that makes machines to cut all types of Honeycomb, Hexcel is one of their customers, Boeing as well.

[Don Johnston]

Are the aluminum honeycomb panels on a Shelby Series 1 similar?

[98SVT - was 06GT]

It's all about going fast in an unlimited machine.

Great history. I've always considered Unlimited Air Races to be the Bonneville of planes. Small teams approaching max performance using their own ideas and work to get there. I hadn't known they limited altitude during turns on speed runs - makes sense so you can't use gravity to help build speed. The G load on the pilot must be tremendous. I remember Art Scholl teaching his brother about the evils of smoking. Tom was home on leave and had taken up smoking. Art had him get in the plane for a ride. After nearly blacking out a couple times in moderate G maneuvers he decided to quit smoking.