| Author | Message | ||
     Daniel Fischer |
On one of the related sites I noticed an S-90 that was for sale, and had been in a landing incident. As I weight time and money against building, I'm also looking at if I build whose, or do I buy a homebuilt thats done Lets accept that GA aircraft can't compete in terms and performance/dollar. But then, planes are gonna get bounced on landings, and sometimes kinda hard. That abovementioned S-90 folded both gears. I've seen 172's drop what has to be 10' and just bounce really hard. So it would seem to be one of: Poor welds /design to weak contrasted to trainer standards / dropped it from 20 feet. Anybody got any thoughts on this? Also, I'd formed the opinion that experimental planes resale value tends to match kit + engine + avionics factored against condition. Or, cost of building, custom, quick, personal, or other, is immmaterial. This tend to be true as well? Thanks folks. dan Fischer dafisch@nortelnetworks.com | ||
| John Harlow |
I feel that building has got to be most of the fun associated with a homebuildt project. If the only reason you are considering a homebuildt is cost than yes it may be better to buy used.I have just completed mine and today I finished flying off the required 25 hours. The whole experience was well worth the effort and I feel now that I have flown it that I could not afford to buy a comperable aircraft for what I have in my Express. I'am sure that I could not sell it for anything close to the cost of a production Cessna 182. I own a 76 Cessna 182 and I can tell you there is no comparison. I feel that the resale price of a homebuildt is less than a production plane of the same caliber but it also can vary a great deal based on the make and model. There are some that command a premium such as Vans RV series, Lancer IV & IVP, and the Express. Based on the number completed and flown the Express is on the lower side at this time but with the increase in completions and satisified owners the price will continuie to go up. This is one very nice flying airplane. I have only made 18 landings to date and all have not been greazers but no ill effects on my gear. My 2 cents John | ||
| Gary Markwardt |
Re: resale value, I would think that planes completed with the builder's assist program would have increased value over kit + engine + avionics. The factory involvement and expert oversight of the airframe construction process should be a big plus on resale. Since there have been several landing gear designs in the prior Express versions, you'd need to know which design failed & how it failed. The latest improvements in the Series 2000 look to be very substantial. Since I just put my wings on today at Olympia, I can't say from personal experience how strong they are. | ||
| Dennis Warner |
I am looking for information/experience with the newer factory aluminum gear. Can anyone tell me about the gear, height, weight, thickness, stiffness, etc. I have been flying my Express for eleven years. It's now time to make some gear changes. Please advise. | ||
| Tom R. Hutchison (Tomhutch) |
Dennis, I have purchased the new gear. I can do some measuring and weighing when I get back to the shop this evening. I don't have a way of measuring the installed height since I don't have them installed yet. Hope this helps, Tom | ||
| Hans Georg Schmid (Hgschmid) |
Tom I just received the new gear - it looks perfect. The only drawback is the weight. The original gear was 17.18 kg (37.87 lbs.), the new gear weighs 29.2 kg (64.37 lbs.). I nevertheless believe it to be so much better than the original version that I gladly accept the additional weight. Hammerhead Aviation, the manufacturer (www.hammerhead-aviation.com) wrote me yesterday: To answer your questions regarding the Landing Gear, it is manufactured out of MIL. SPEC. Mill Direct 7075 Aluminum Alloy. The metal is machined in the T-6 condition and then sent to our Certifed Heat Treaters to be annealed to the condition of "O" for bending, once the bending has been achieved the Landing Gear then returns to the Heat Treaters where it is returned to the T-6 condition. After final measurements have been brought into tolerances the Landing Gear is sanded to a finish of 150 grit. The Landing Gear is then Non destructive tested using a Dye-Penetrant Inspection to insure that no cracking occured to the metal during bending and heat-treating. Here is the information minus the proprietary data: Aircraft: Express Material Thickness: 1.5" Material Width: 6.0" Outside Gear Width: 69.0" Total Gear Height: 31.625" Top Flat: 28.0" Leg Bottom Width: 2.125" Camber Adjust: 5.44 Deg. Axle Type: 6.00 X 6 Gear Weight: 70.77 Lbs 3G Stress: 39480 Psi I need the paperwork for the gear (stress analysis) as the authorities in Switzerland want most probably to see it, and Hammerhead Aviation assured me Larry would send it directly to me. As far as I can see at the moment the new gear fits perfectly. I can't however say whether it has exactly the same height as the old gear as I havn't checked yet. Best regards from rainy Switzerland HG Schmid www.aeroexplorer.biz | ||
| Anonymous |
don't know exact heights, but take a look at the factory demonstrator and recent builder completions to get a rough idea to help gauge or compare to the old gear. | ||
| Tom R. Hutchison (Tomhutch) |
Thanks Hans, you saved me from having to figure out all that info. You definitely gain some height. See http://www.express-builder.com/gallery/album07/aax for a picture of the factory demonstrator with the new gear. In fact you will want the new nose yoke that has a bend to raise the nose up to be level with the new gear. I will upload a pic of that when I get home. Tom | ||
| Larry Hoppe |
A note of caution: Both Grove and Hammerhead are producing all their landing gear from 7075 T6 aluminum. According to the book "Aluminum-Properties and Physical Metallurgy" "The higher strength alloys such as 7075 are quite susceptible to short transverse stress corrosion cracking in the peak aged T6 temper. This generally limits the application of T6 temper alloys to structures in which there is no conceivable source of short transverse stress." We ordered Al gear from Grove before the factory announced the change but ordered 7050 T7651 which provides much better corrosion resistance with the same strength as 7075 T6. | ||
| Tom R. Hutchison (Tomhutch) |
Larry Hoppe, What would you suggest for corrosion protection for the 7075 alloy? I was tentively planning on having my legs anodized and maybe powder coated for good measure. Tom | ||
| Tom R. Hutchison (Tomhutch) |
To answer my own question, I contacted Hammerhead the manufacturers of the new AL gear. This is their response: The most common method of finishing aluminum landing gear legs is to epoxy prime followed by a urethane top coat. With our certified customers it is common to anodize, but only as a corrosion preventive measure, as the anodize is "clear". The material your landing gear is constructed of is 7075-T6, it is our experience that other aluminum alloys accept an anodize finish far better than 7075, such as the 3000, 5000, 6000, series, unfortunately none of these possesses the mechanical properties necessary for the demanding environment of a landing gear. 7075 will accept color dye anodize but will most likely be a little less brilliant. It would be wise to check with the platter and explain the alloy prior to starting, he may be able to adjust his process to give you the best results. as part of the anodize process is to induce corrosion and then stop it, it may be possible to increase the time in the tank prior to rinsing and sealing. Another option is powder coating, their are many new methods that produce finishes that look like candy color anodize but have greater durability and can be applied to almost any metal. The one thing to be careful of while power coating is Temperature, part of our heat treat is to artificially age the aluminum, this process is done @ 375 to 425 degrees for 12 to 24 hours. To avoid changing the finial temper of the gear it's a good idea to remain below 375 degrees when cooking off the powder coat. I hope this was of some use to you, and wish you well with your kit. Hammerhead Aviation, Robert Veronneau owner Larry Olsen also suggested NOT powdercoating because of the possibility of damaging the heat treating. Tom | ||
| Gary Markwardt |
I recently installed the new Aluminum gear. It was painted with epoxy primer and top coated with the same urethane used on the plane. To get an idea of the change in height, I took a photo of the new gear on the LH side & the old gear on the LH side. Here it is:\image I'm still waiting for the raised nose wheel yoke from Express. | ||
| Gary Markwardt |
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| Brynjar Thordarson (Benny) |
Just for kicks! Which one is on the LH side? Rgds. BENNY | ||
| Anonymous |
the new gear seems to be on the left side making it stand higher.. the old fiberglass bear appears to be on the right. | ||
| Gary Markwardt |
Oops! Aluminum gear is on RH wing (left side of picture), old gear on LH wing. The plane stands quite a bit higher with the new gear. Between figuring out how to post a picture & telling my right from left, I'm all confused!!! Gary |