DC does have advantages for high voltage power transmission. The problem in Edison's day was that there was no way of converting a high current at low voltage to a low current at high voltage or to do the reverse. This was important because resistive losses in transmission were proportional to the square of the current. However, it could be done with AC using transformers. Now one has thyristors and other high power semiconductor devices that make DC power conversion economically feasible.
Aluminium in the aeroplanes?
- Thread starter Elmas
- Start date
Ad: This forum contains affiliate links to products on Amazon and eBay. More information in Terms and rules
Around 10960, the vacuum tube division of GE was placing full page ads in Scientific American extolling the virtues of vacuum tubes. Typical headings were "Must you pay the high cost of miniaturization?". This was around the time that the technology was being developed for the batch manufacture of high performance silicon transistors. This crucial development quickly made vacuum tubes completely obsolete for most applications. It also paved the way for integrated circuits.
Evidently the concept of alloys escapes the writer.
GregP
Major
Apparently so, Capt.He is still right about at least one thing ... there is little to no pure Aluminum in an airplane.
Last edited:
drgondog
Major
NYT continues track record for accurate reporting even today..
Shortround6
Major General
I would note that while the 1913 Peugeot race car engine (first race car engine to use 4 valves per cylinder) used an aluminium crankcase the cylinder block and head were iron and the pistons were billet steel. An aero engine entered in the 1913 Kaiserpries aero-engine competition was refused entry because it used aluminium pistons. The 1914 Mercedes Grand Prix engines were tested with both cast iron and aluminium pistons and while the aluminium ones gave no trouble in testing the drivers all chose to use the cast iron pistons in competition.
The writer of the article was indeed wrong but he was not alone in his thinking at the time.
The writer of the article was indeed wrong but he was not alone in his thinking at the time.
GregP
Major
Nice bits of info, Shortround.
Balljoint
Senior Airman
As did B-29 motor mounts.
Plenty of magnesium used in aircraft manufacture nowdays. Helicopter gearbox cases, turbine engine gearbox cases, wheel hubs. It was quite popular in the 60's jet era. The Hawker Hunter used quite a bit in the airframe, as, I believe, did the Mig21.
razor1uk
Staff Sergeant
And we haven't even started vacuum casting metals in space/in a Zero G environment yet - at least not in anything more than possibly nano/minute amounts (more likely tried with plastics/resins) in a shuttle or the ISS... let alone the study the effects of differing gravities acting upon the dendritic crystaliastion processes.
Or how about linear magnetic poppet valves instead of pneumatic ones.
...or an poppet valveless cylinder head that runs at 1/8 crank speed for a 4 stroke (half it for a 2 stroke version) thats been banging around inside my bonce for 15+ years - possibly needs sinstered ceramic and or metalic hot forging to creat the 'valve gubbins'
Or how about linear magnetic poppet valves instead of pneumatic ones.
...or an poppet valveless cylinder head that runs at 1/8 crank speed for a 4 stroke (half it for a 2 stroke version) thats been banging around inside my bonce for 15+ years - possibly needs sinstered ceramic and or metalic hot forging to creat the 'valve gubbins'
Last edited:
swampyankee
Chief Master Sergeant
- 4,031
- Jun 25, 2013
The engine I worked on -- the ALF-502 (my signature is on some of the test reports submitted for the certification) used quite a bit of magnesium alloy, in the compressor housing (thorium-magnesium alloys retain their strength better at high temperatures than aluminum ones) and the fan frame. The USAF decided it didn't like magnesium, so there had to be a lot of work redesigning the compressor housing and the fan frame.
I believe the F8U Crusader and T-38 used quite a bit of magnesium sheet in their construction. Also, I think there's somebody selling a magnesium bicycle frame.
Most aircraft still use quite a bit of steel, in their landing gear. It's better for that sort of structure than just about anything else.
GrauGeist
Generalfeldmarschall zur Luftschiff Abteilung
Volkswagon and Porsche both used Magnesium alloys in their air-cooled engine cases...
fastmongrel
1st Sergeant
razor1uk
Staff Sergeant
Their Segal alloy 'recipie' is so so good at preventing corrosion, that they have to ceramic coat/enamal base coat the frame once welded/brazed; well I suppose it all helps - mag notoriosly corrodable in its pure form, makes real good sparks too like titanium, though a few too many and pure mag consumes itself. Mind-due, 1.2 kg for the bare ready frame (without axle bearings, crank, gears etc) is ferkin little finger light - whole bike is easily under 10kg!
Moto Guzzi made its dustbin fairings for their 1950's V8 GP bike out of mag, with a green anodised anti-corrosion coating, Velocette, Norton NSU also used to use quite a bit of Electron (mag alloy) for their select race components. Most bike racing branches of the major factories still use mag alloys quite widely, let alone thinking about mag usages in the car racing worlds.
Moto Guzzi made its dustbin fairings for their 1950's V8 GP bike out of mag, with a green anodised anti-corrosion coating, Velocette, Norton NSU also used to use quite a bit of Electron (mag alloy) for their select race components. Most bike racing branches of the major factories still use mag alloys quite widely, let alone thinking about mag usages in the car racing worlds.
Last edited:
Airframes
Benevolens Magister
I can still remember the horrendous white fireball, when that magnesium Honda F1 car crashed and burned.
fastmongrel
1st Sergeant
Actually for a Road Race frame thats quite porky even my carbon MTB frame only weighs 200 grams more and thats not even considered particulary light.
GregP
Major
I have seen several pics where an F-8 Crusader hit the deck with a flat tire and the Magnesium wheels burst into flames from the sparks. The airframe continued over the side and the pilot ejected and was rescued by the guard chopper.
Magnesium should not be allowed in military aircraft and I would decline to ride in a civil aircraft employing Magnesium if I knew it. The only bad experience I have has with it was my fault. I cracked a magnesium wheel that went to our Hispano Ha.1112 trying to get a tire seated on the bead. We decided to have a couple of new wheels made from Aluminum and have since done that (they are on the plane at this time). We have one mag Ha.1112 wheel left from that issue and it now serves as the spare wheel for our static Bf 109G.
All I can tell you is not to hit a magnesium wheel too hard with a deadblow hammer trying to seat a tire. It'll crack. Much better to use a real tire mounting machine, thugh I'm not sure THAT wouldn't also crack it. There is probably a special process specified for tire mounting. The only reason I didn;t feel overly bad about it was I was being watched by long-time A&P's who had no comments at all until the wheel cracked. They said they would have done the same thing.
At least the new Aluminum wheel aren't tahht delicate and are stronger to boot. From lifting both the ALuminum wheels are slightly heavier. but not much. I didn't weigh them separately to find out because I wasn't all that interested. The Hispano has no wing gins and we removed the outer wing panel tanks, soi it is already considerebly lighter than a service-ready Ha.1112 Buchon. I have no doubt that the small extra weight of the ALuiminum wheels is negligible compared with removal of the gund and fuel tanks. We will also fit a 3-blade prop in lieu of the 4-blade unit and that should be lighter, too.
We also have moved the hydraulic pump from the engine compartment to the rear fuselage behind the wing training edge. That gets the hydraulic oil away from the engine entirely.
Magnesium should not be allowed in military aircraft and I would decline to ride in a civil aircraft employing Magnesium if I knew it. The only bad experience I have has with it was my fault. I cracked a magnesium wheel that went to our Hispano Ha.1112 trying to get a tire seated on the bead. We decided to have a couple of new wheels made from Aluminum and have since done that (they are on the plane at this time). We have one mag Ha.1112 wheel left from that issue and it now serves as the spare wheel for our static Bf 109G.
All I can tell you is not to hit a magnesium wheel too hard with a deadblow hammer trying to seat a tire. It'll crack. Much better to use a real tire mounting machine, thugh I'm not sure THAT wouldn't also crack it. There is probably a special process specified for tire mounting. The only reason I didn;t feel overly bad about it was I was being watched by long-time A&P's who had no comments at all until the wheel cracked. They said they would have done the same thing.
At least the new Aluminum wheel aren't tahht delicate and are stronger to boot. From lifting both the ALuminum wheels are slightly heavier. but not much. I didn't weigh them separately to find out because I wasn't all that interested. The Hispano has no wing gins and we removed the outer wing panel tanks, soi it is already considerebly lighter than a service-ready Ha.1112 Buchon. I have no doubt that the small extra weight of the ALuiminum wheels is negligible compared with removal of the gund and fuel tanks. We will also fit a 3-blade prop in lieu of the 4-blade unit and that should be lighter, too.
We also have moved the hydraulic pump from the engine compartment to the rear fuselage behind the wing training edge. That gets the hydraulic oil away from the engine entirely.
Last edited:
razor1uk
Staff Sergeant
!! ok, well that'd only require a small amount of helium gas being sealed inside to make it lighter... and up the price - to bad helium escapes/bonds to other elements and so 'dissapates' sp easily
That reduces that aircraft that you can fly on to almost nil...
Magnesium in Aerospace
Magnesium and its alloys are routinely used in most (if not all) helicopter and transport aircraft now. I think you would be lucky if the aircraft you were on didn't have large quantities of it.
FLYBOYJ
"THE GREAT GAZOO"
I'd say about 80 - 90% of the aircraft I've worked on in 35 years (to include airliners, military, GA and corporates) had some components or parts made from magnesium.
