GordoP Posted February 11 Posted February 11 Hello I would like to ask if anyone has had any experience replacing the tail boom on the Aussie manufactured Sapphire?? I understand that the material was literally 5inch aluminium ag pipe with wall thickness of either 1.2 or 1.6mm any advice gratefully received! cheers GordoP
Litespeed Posted February 12 Posted February 12 It would not be plain ag pipe but a specific grade of alloy tube for aviation spec. Others should have the actual specs, do not shop at Bunnings Aerospace for your parts. Cheers Phil
Area-51 Posted February 12 Posted February 12 During conversations with Dean Winton a few years ago he presented the possibility of wrapping the boom with resin carbon fibre to provide additional strength.
onetrack Posted February 12 Posted February 12 (edited) The tubing will likely be precision seamless drawn tubing, made from aviation grade alloy, heat treated and tempered to a British or American Standard. The precision finish is required to ensure minimal unevenness in wall thickness. No aluminium agricultural pipe for carrying water would have any degree of strength, it is seamed (a weakness), and it would have a large variation in wall thickness over each length. However, you can purchase Unipipe, which is produced in a range of aluminium alloys, some of which are designed for high pressure piping, and which may have adequate strength. The "T" reference in the aluminium grades refers to the heat treatment, with T6 being the strongest and toughest aluminium grade - but it is also the grade with the lowest level of elongation. Elongation is the figure that shows just how much a metal stretches before it fractures. Lower strength metals will generally have higher elongation rates than high strength metals, but this is not always 100% the case. Good corrosion resistance is also a highly desirable characteristic of any aluminium material used in an aircraft. Aircraft Materials WWW.AIRCRAFTMATERIALS.COM Aluminium 6060 Data Sheet - BlueScope Distribution WWW.BLUESCOPEDISTRIBUTION.COM.AU 6060 is a medium strength heat treatable alloy with good corrosion resistance, weldability and responsiveness to anodising. See the data sheet here. Edited February 12 by onetrack
GordoP Posted February 12 Author Posted February 12 3 hours ago, Litespeed said: It would not be plain ag pipe but a specific grade of alloy tube for aviation spec. Others should have the actual specs, do not shop at Bunnings Aerospace for your parts. Cheers Phil Hi Phil thanks for your response interestingly I have seen some correspondence from the previous owner to the manufacturer that seems to indicate that the tubing was “ 5 inch irrigation pipe with 1.2 or 1.6 wall thickness with early tube being seam welded and the later extruded” I’m trying to track the original product via Toro and Capral to see what the alloy was? The project came with a severed boom at the fuselage junction with a 700mm remnant remaining glued inside the fuselage!? 1
BrendAn Posted February 12 Posted February 12 Irrigation tube was used in a lot of early ultralights I have been told. 1 1
Red Posted February 12 Posted February 12 The CFM Shadow microlights used Irrigation pipe, it wouldnt surprise me if used on other designs 1 1
BrendAn Posted February 12 Posted February 12 10 hours ago, onetrack said: The tubing will likely be precision seamless drawn tubing, made from aviation grade alloy, heat treated and tempered to a British or American Standard. The precision finish is required to ensure minimal unevenness in wall thickness. No aluminium agricultural pipe for carrying water would have any degree of strength, it is seamed (a weakness), and it would have a large variation in wall thickness over each length. However, you can purchase Unipipe, which is produced in a range of aluminium alloys, some of which are designed for high pressure piping, and which may have adequate strength. The "T" reference in the aluminium grades refers to the heat treatment, with T6 being the strongest and toughest aluminium grade - but it is also the grade with the lowest level of elongation. Elongation is the figure that shows just how much a metal stretches before it fractures. Lower strength metals will generally have higher elongation rates than high strength metals, but this is not always 100% the case. Good corrosion resistance is also a highly desirable characteristic of any aluminium material used in an aircraft. Aircraft Materials WWW.AIRCRAFTMATERIALS.COM Aluminium 6060 Data Sheet - BlueScope Distribution WWW.BLUESCOPEDISTRIBUTION.COM.AU 6060 is a medium strength heat treatable alloy with good corrosion resistance, weldability and responsiveness to anodising. See the data sheet here. Have you been involved with ultralight aircraft . I am guessing you are ga background
GordoP Posted February 12 Author Posted February 12 10 hours ago, Area-51 said: During conversations with Dean Winton a few years ago he presented the possibility of wrapping the boom with resin carbon fibre to provide additional strength. Thanks area-51 I guess that confirms that the area at the junction of the fuselage and boom was a possible weak point? I would think there have been other Sapphire incidents where the boom has been damaged, I’d be keen to hear from anyone who has attempted to remove / replace the boom and how they did it..?? Regards GordoP
facthunter Posted February 13 Posted February 13 It's obvious that the greatest BENDING moment is at the forward part of the boom. In similar situations (Stress points) SPARS are made stronger by having caps or doublers. With tubes you can insert another tube inside. Check out a thruster in that area. Nev
GordoP Posted February 13 Author Posted February 13 8 hours ago, Red said: The CFM Shadow microlights used Irrigation pipe, it wouldnt surprise me if used on other designs Hi Red any chance you could find out the alloy used on the CFM? regards GordoP
GordoP Posted February 13 Author Posted February 13 5 minutes ago, facthunter said: It's obvious that the greatest BENDING moment is at the forward part of the boom. In similar situations (Stress points) SPARS are made stronger by having caps or doublers. With tubes you can insert another tube inside. Check out a thruster in that area. Nev Thanks Nev, will do
Thruster88 Posted February 13 Posted February 13 Thrusters have a 4inch main tube, no doublers but it is well braced .
facthunter Posted February 13 Posted February 13 Yes they are substantial and you check that area pre flight. I think there's a mod there. Nev
BrendAn Posted February 13 Posted February 13 the bloke that bought the rights to sapphires lives in bendigo. he was building them so there is a good chance he may have a fuse boom and the information on how to strengthen that area. 1
facthunter Posted February 13 Posted February 13 I don't think they were ever strengthened but that doesn't stop it from being a good idea. Like a strutless wing the most bending stress in near the root.. Nev 1
BrendAn Posted February 13 Posted February 13 8 minutes ago, facthunter said: I don't think they were ever strengthened but that doesn't stop it from being a good idea. Like a strutless wing the most bending stress in near the root.. Nev I don't know either but he would be the man to ask. He is well known but I forget his name. I have a contact who knows him.
Red Posted February 13 Posted February 13 7 hours ago, GordoP said: Hi Red any chance you could find out the alloy used on the CFM? regards GordoP Hello Gordo, Sorry I don't know the spec. The designer David Cook states the use of a standard and available in the UK irrigation pipe in his book "Flying from My Mind" I had a copy of the book but lent it out never to be seen again but I don't think he states the actual spec in the book. Bare in mind it was an 80s design. I owned and flew a Shadow for some years, fantastic view and very benign handling. There is a shadow facebook site at https://www.facebook.com/groups/263902687415672 But I dont have a facebook account so can't ask questions there...good luck in your search 1
facthunter Posted February 13 Posted February 13 Very clean and efficient and a bit elevator sensitive. Everyone I knew has passed on. Fan cooled 447 Rotax. 2 different versions of the plane as I recall. Worth having one in my opinion. Nev 1
Red Posted February 13 Posted February 13 45 minutes ago, facthunter said: Very clean and efficient and a bit elevator sensitive. Everyone I knew has passed on. Fan cooled 447 Rotax. 2 different versions of the plane as I recall. Worth having one in my opinion. Nev Actually at least 3 different named versions (shadow, streak shadow, starstreak shadow), mine had a 503 there are 3 at the airfield Im at now, all have different engines (503 582 912) there are 2 different wing lengths and 2 different body widths though most are the narrow version. I don't remember any pitch sensitivity though flutter was a problem on some and there was a friction mod to alleviate it. I went a different way and lightened the elevator by using light covering that required no paint as I believe the flutter was a balance problem caused by the elevatror trim servo being inside the elevator and then builders using lots of paint...the flutter was quite scary when experienced but I cured it. Apologies for the thread drift. 2 1
facthunter Posted February 14 Posted February 14 I'm only talking about Saphire's. I have NO knowledge of the Streak shadows etc. Nev 1 1
GordoP Posted February 14 Author Posted February 14 20 hours ago, Blueadventures said: This guy had tube for sale on 2nd January. Thanks for the lead!…I’m just trying to join up to that group to chase the contact details, could be lucky and have some 5 inch tube!? Gordo 1
GordoP Posted February 14 Author Posted February 14 19 hours ago, BrendAn said: I don't know either but he would be the man to ask. He is well known but I forget his name. I have a contact who knows him. Hi BrendAn if you’re able to track the guy through your contact that would be greatly appreciated!! Cheers Gordo
BrendAn Posted February 14 Posted February 14 4 minutes ago, GordoP said: Hi BrendAn if you’re able to track the guy through your contact that would be greatly appreciated!! Cheers Gordo Will do 1
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