Stranger things have been known to happen...Originally posted by f1steveuk
What? You mean like an Alfa flat 12? Surely not?;)
;)
Hill GH2 pictures (merged)
Started by
Alexandre
, Nov 27 2004 18:16
73 replies to this topic
#51
Twin Window
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Posted 10 November 2008 - 22:17
;)
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#52
PeterElleray
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Posted 10 November 2008 - 22:24
Hi David - you make some interesting points, and although i cant speak for the GH2, many years ago i talked to Maurice Phillippe and Brian Lisles about the 008 tyrrell, the side pontoons of which were 9.5" high. They was pretty happy with its stiffness (at the time, in context) - the trick being to tie in the shallow but broad pontoons - in themselves adequately stiff - together with the fuel cell, dash roll hoop and the forwards transverse diaphrams in such a way that there is no weak link in the assembly. i believe 008 achieved this - at least that was what i was told!
Now, the side pontoons on the Hill, triangular in section, should have been inherently stiff, but, take a look at the bare tub, and decide for yourself if they are tied together well forwards of the dash hoop - where does the leverage from the front spring dmapers go for instance? Another one to look at is the Hesketh 308C/Williams FW05. Where do the rocker arm reaction loads go? The later versions of the tub were heavily reinforced here - that should give us a clue. infact the car that runs as a 308C in TGP is to this spec.
The Brabham, and the Surtees, in contrast, seem to look more right and more elegant to me as the years pass, not just because of the triangular pontoons, but the detail of the footbox - take a look on "gurneyflap".
Bonde - what do you reckon?
peter
Now, the side pontoons on the Hill, triangular in section, should have been inherently stiff, but, take a look at the bare tub, and decide for yourself if they are tied together well forwards of the dash hoop - where does the leverage from the front spring dmapers go for instance? Another one to look at is the Hesketh 308C/Williams FW05. Where do the rocker arm reaction loads go? The later versions of the tub were heavily reinforced here - that should give us a clue. infact the car that runs as a 308C in TGP is to this spec.
The Brabham, and the Surtees, in contrast, seem to look more right and more elegant to me as the years pass, not just because of the triangular pontoons, but the detail of the footbox - take a look on "gurneyflap".
Bonde - what do you reckon?
peter
#53
Bonde
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Posted 11 November 2008 - 14:05
Peter,
I can only agree with your observations - I would also essentially look at a chassis of this nature as being two closed-section beams tied together at their ends (and ocassionally along the way as well, for instance at the front roll hoop) and then being loaded in differential bending. The fabricated 'horns' carrying the front spring/dampers and upper wishbones are outrigged pretty far and thus provide a lot of leverage to twist the GH2 side beams, and they also sit some distance aft of the chassis front bulkhead, so that may have been a weak area due to the many load introduction off-sets. In this day and age we would probably exploit some scheme of remote location of the spring/damper units in order to locate load introduction points closer to where we find room for our main structure. Still, not having done the calcs, the GH2 structure may have been 'stiff enough', even though it certainly doesn't look ideal. I don't suspect the front roll-hoop structure really provides much in the way of a connection between the side beams - it looks a lot better on the 008 - actually the only thing that looks slightly 'iffy' to me on the 008 is the upper attachment to the engine, simply due to the relatively small diameter of the tubes that react the longitudinal loads there, but again not having done the calcs, they may well be 'stiff enough'.
The way the front hoop stays on the GH2 cross half-way between the apex of the hoop and at their feet on the chassis seems to me to add an uncessary node in the system - I would have configured the stays as an inverted vee with its apex at the top of the hoop. A lot of seventies cars have hoop stays configured in the way used on the GH2; the only advantage I can see off-hand is that it does provide some degree of in-plane lateral triangulation without having to locate the stays right at the top of the hoop, where the node may risk being worn away if the car scrapes inverted along the tarmac. Either that or I may have overlooked some other advantage to crossing the stays, rather than letting them meet at top of the hoop?
I'll have to sift through my old Autosports to see if I can find a picture of what the GH2 structure looks like where the engine is attached before I can comment on that area.
Remi,
If you're reading this thread: Do you have any photos of the 'naked' GH2 chassis other than those on Gurneyflap?
So, just to elaborate a bit on Dave's and Peter's observations for those with a just a passing structural interest: Moving the beams further apart increases differential bending (aka 'torsional') stiffness, simply by increasing the moment arm length available for bending moment resistance, but as Peter pointed out, this requires sufficient stiffness of the transverse bulkeads and their connections to the side beam longerons to work as intended (and as always load introduction and distribution is always a challenge). When there is no more structural overall width available, or no restriction of height, inceasing individual beam section, particularly in height, is more efficient, as the section modulus increases to the third power of the linear dimension normal to the axis around which we bend (strength to the second power), all else being equal (shear/compression buckling stability due to thin, large panels eventually comes into play).
Chassis such as the GH2, the Tyrrell 008, Hesketh 308C/Williams FW05 and in USAC Bob Riley's mid-seventies Coyotes and Wildcats all had shallow but broad and (relatively) wide-spaced side beams, and some were race winners (008 and Riley's cars). As Peter pointed out, the devil is in the details - how to make the beams work together and how major loads are fed into them - a thin sheet floor pan didn't do much in this respect, so bulkheads and behind-driver fuel tank box had to do it. A sucessful (measured in race wins) flat-wide chassis that comes to mind is the Lola T330/332 F5000/single seat Can-Am.
Quite a few sports-prototype chassis over the years have also had the flat-wide architecture, some sucesfully, others not.
I suppose that one of the things that helped the flat-wide chassis of the pre-ground effect seventies work reasonably well was the use of, by modern standards, very softly sprung suspension so that the deflection of the chassis remained minor relative to that of suspension springs, and that the wishbone loads remained pretty much in the horizontal plane, where each side beam was quite stiff due to great width, and where the floor structure helped, too.
On paper the 308C/FW05 may have worked by merit of individually 'stiff enough' side beams, but, as Peter pointed out, the 308C later had a transversal bridge added just behind the front rocker mounts. Adding weight high-up in a chassis is never done without a good reason...
As the wheel rates greatly increased with the introduction of ground effect aerodynamics, structural inadeqaucies became readily apparent, as Dave points out, not least on the Lotus T79. Getting stiffness into an aerodynamically-driven small (narrow) chassis cross section naturally led to increasing the side beam height right up to the edge of the cockpit opening, but, with hindsight, it was a surprisingly long time in coming, and structurally the Lotus T79 certainly seems to me a retrograde step relative to the T78. I would guess (disregarding the tubular front suspension supports) that both the T77 and the T78 were stiffer in torsion than the T79 (and I also speculate that poor Ronnie Peterson would have been killed instantly in a T79, but there may not have been a fire - seeing how badly the T78 honeycomb sandwich tub front was damaged by the impact on the Armco and its supports, I fear the single-skinned T79 nose would have fared even worse). Carbon fibre materials technology was then the next stage in obtaining stiffness by using material with vastly higher modulus of elasticity (and higher strength, too) from a small chassis cross-section, and yet pioneering Barnard stayed loyal to the shallow, open, exposed cockpit area for aerodynamic flexibility (which didn't appear to be used much anyway) for a surprisingly long time.
At the end of the day racing car design (indeed, all engineering!) is a matter of finding the best compromise for the intended purpose, so structurally it was (and still is, as nothing is infinitely stiff) a question of 'stiff enough', which allowed the flat tub/tall non-structural "conning tower" architecture to prosper for a little while. I suppose its advantages were seen as aerodynamic (small cross section not masked by the wheels, clean flow to rear wing) and a low centre of gravity.
From the safety aspect, the driver did seem to be very exposed when sat 'on' rather than 'in' the tub, but tall, narrow structural cockpit sides back then typically would have meant thin aluminium sheet and little else, which wouldn't have provided much resistance against side impact and would have increased the risk of the driver getting trapped in the chassis, which was the last thing you wanted back in the days when fire was the big killer. Once we got the fuel out of harm's way (as in the T79 architecture) the risk of fire was greatly reduced, and then any lateral structure could be better used for sacrificial impact protection rather than for housing fuel. Still, aluminium honeycomb panels were already in use back then (1976 McLaren M26 used a lot of it), so again with the benefit of hindsight, it is perhaps rather surprising that it wasn't used for structural cockpit fairings sooner, but the need simply wasn't there from a structural point of view when the fuel mostly lived in the side box beams. The 1979 Fittipaldi F6 had tall aluminium honeycomb side panels (and the Wolf WR9 also to a certain extent) and all the fuel behind the driver, but these cars were not succesful (for other reasons). Had they been, I suspect all subsequent cars would have had tall side structural side panels from 1980, but that, of course, is pure speculation. BTW, IIRC Chapman went backwards structurally with the T79 because he found honeycomb sandwich panels too difficult to stress, fabricate, assemble and repair, so it may have been a simple case of Team Lotus' seemingly persistent lack of time AND money...He and Lotus did learn from that mistake relatively quickly, though, (with help from Peter Wright) so, not surprisingly, Lotus had the first deep-sided carbon composite tub ready at the same time as Barnard's pioneering MP4/1...
Come to think of it, I can't OTTOMH remember a driver being killed or seriously injured in a shallow chassis car due to lack of lateral protection above hip height, but there may have been some - perhaps in Lola T330/T332s as there were so many of those in front line action?
I've always been a bit surprised that so few used a triangular section for the box beam longerons - easy to build and with its truss-like cross section it could rely less on closely spaced bulkheads for torsional stiffness relative to a rectangular or other polygon shape, which would have been handy in the days when the fuel bags typically resided there. I also just happen to like the shape visually...
Peter,
Aren't Murray's triangular beam chassis just neat? I wouldn't be surprised if they are impressively stiff, even by modern standards. The Ken Sears/John Surtess TS19/20 was also quite neat and visually pleasing, and probably also very stiff for its generation. Another thing I find very neat is the way that Murray obtained a degree of progressive pullrod-operated springing simply by locating the pivot of the bottom 'tappet' high on the chassis, rather than using a massively complicated 'spider' on the upper wishbone, as on Lotus T72/76, Parnelli VPJ1, Ensign MNo75-77 and Amon AF1 - Murrays method was also used on the Surtess but in a somewhat less elegant manner (although rather I do like Surtees' wide-based lower rear wishbone and upper parallel links).
Anyway, on the subject of suspension members, with wishbones being 'wear items' one wants them to be simple items - on our Formula Fords we let the pullrod pick up directly on the uprights (also at the front), so our wishbones are just tubes and laser-cut lug plates, all of them non-handed (oops - sorry about the shamless plug and thread detour...)
Peter,
it's just great to have somone of your awesome present-day design stature show such deep affection and interest for our sport's history - keep it up!
I can only agree with your observations - I would also essentially look at a chassis of this nature as being two closed-section beams tied together at their ends (and ocassionally along the way as well, for instance at the front roll hoop) and then being loaded in differential bending. The fabricated 'horns' carrying the front spring/dampers and upper wishbones are outrigged pretty far and thus provide a lot of leverage to twist the GH2 side beams, and they also sit some distance aft of the chassis front bulkhead, so that may have been a weak area due to the many load introduction off-sets. In this day and age we would probably exploit some scheme of remote location of the spring/damper units in order to locate load introduction points closer to where we find room for our main structure. Still, not having done the calcs, the GH2 structure may have been 'stiff enough', even though it certainly doesn't look ideal. I don't suspect the front roll-hoop structure really provides much in the way of a connection between the side beams - it looks a lot better on the 008 - actually the only thing that looks slightly 'iffy' to me on the 008 is the upper attachment to the engine, simply due to the relatively small diameter of the tubes that react the longitudinal loads there, but again not having done the calcs, they may well be 'stiff enough'.
The way the front hoop stays on the GH2 cross half-way between the apex of the hoop and at their feet on the chassis seems to me to add an uncessary node in the system - I would have configured the stays as an inverted vee with its apex at the top of the hoop. A lot of seventies cars have hoop stays configured in the way used on the GH2; the only advantage I can see off-hand is that it does provide some degree of in-plane lateral triangulation without having to locate the stays right at the top of the hoop, where the node may risk being worn away if the car scrapes inverted along the tarmac. Either that or I may have overlooked some other advantage to crossing the stays, rather than letting them meet at top of the hoop?
I'll have to sift through my old Autosports to see if I can find a picture of what the GH2 structure looks like where the engine is attached before I can comment on that area.
Remi,
If you're reading this thread: Do you have any photos of the 'naked' GH2 chassis other than those on Gurneyflap?
So, just to elaborate a bit on Dave's and Peter's observations for those with a just a passing structural interest: Moving the beams further apart increases differential bending (aka 'torsional') stiffness, simply by increasing the moment arm length available for bending moment resistance, but as Peter pointed out, this requires sufficient stiffness of the transverse bulkeads and their connections to the side beam longerons to work as intended (and as always load introduction and distribution is always a challenge). When there is no more structural overall width available, or no restriction of height, inceasing individual beam section, particularly in height, is more efficient, as the section modulus increases to the third power of the linear dimension normal to the axis around which we bend (strength to the second power), all else being equal (shear/compression buckling stability due to thin, large panels eventually comes into play).
Chassis such as the GH2, the Tyrrell 008, Hesketh 308C/Williams FW05 and in USAC Bob Riley's mid-seventies Coyotes and Wildcats all had shallow but broad and (relatively) wide-spaced side beams, and some were race winners (008 and Riley's cars). As Peter pointed out, the devil is in the details - how to make the beams work together and how major loads are fed into them - a thin sheet floor pan didn't do much in this respect, so bulkheads and behind-driver fuel tank box had to do it. A sucessful (measured in race wins) flat-wide chassis that comes to mind is the Lola T330/332 F5000/single seat Can-Am.
Quite a few sports-prototype chassis over the years have also had the flat-wide architecture, some sucesfully, others not.
I suppose that one of the things that helped the flat-wide chassis of the pre-ground effect seventies work reasonably well was the use of, by modern standards, very softly sprung suspension so that the deflection of the chassis remained minor relative to that of suspension springs, and that the wishbone loads remained pretty much in the horizontal plane, where each side beam was quite stiff due to great width, and where the floor structure helped, too.
On paper the 308C/FW05 may have worked by merit of individually 'stiff enough' side beams, but, as Peter pointed out, the 308C later had a transversal bridge added just behind the front rocker mounts. Adding weight high-up in a chassis is never done without a good reason...
As the wheel rates greatly increased with the introduction of ground effect aerodynamics, structural inadeqaucies became readily apparent, as Dave points out, not least on the Lotus T79. Getting stiffness into an aerodynamically-driven small (narrow) chassis cross section naturally led to increasing the side beam height right up to the edge of the cockpit opening, but, with hindsight, it was a surprisingly long time in coming, and structurally the Lotus T79 certainly seems to me a retrograde step relative to the T78. I would guess (disregarding the tubular front suspension supports) that both the T77 and the T78 were stiffer in torsion than the T79 (and I also speculate that poor Ronnie Peterson would have been killed instantly in a T79, but there may not have been a fire - seeing how badly the T78 honeycomb sandwich tub front was damaged by the impact on the Armco and its supports, I fear the single-skinned T79 nose would have fared even worse). Carbon fibre materials technology was then the next stage in obtaining stiffness by using material with vastly higher modulus of elasticity (and higher strength, too) from a small chassis cross-section, and yet pioneering Barnard stayed loyal to the shallow, open, exposed cockpit area for aerodynamic flexibility (which didn't appear to be used much anyway) for a surprisingly long time.
At the end of the day racing car design (indeed, all engineering!) is a matter of finding the best compromise for the intended purpose, so structurally it was (and still is, as nothing is infinitely stiff) a question of 'stiff enough', which allowed the flat tub/tall non-structural "conning tower" architecture to prosper for a little while. I suppose its advantages were seen as aerodynamic (small cross section not masked by the wheels, clean flow to rear wing) and a low centre of gravity.
From the safety aspect, the driver did seem to be very exposed when sat 'on' rather than 'in' the tub, but tall, narrow structural cockpit sides back then typically would have meant thin aluminium sheet and little else, which wouldn't have provided much resistance against side impact and would have increased the risk of the driver getting trapped in the chassis, which was the last thing you wanted back in the days when fire was the big killer. Once we got the fuel out of harm's way (as in the T79 architecture) the risk of fire was greatly reduced, and then any lateral structure could be better used for sacrificial impact protection rather than for housing fuel. Still, aluminium honeycomb panels were already in use back then (1976 McLaren M26 used a lot of it), so again with the benefit of hindsight, it is perhaps rather surprising that it wasn't used for structural cockpit fairings sooner, but the need simply wasn't there from a structural point of view when the fuel mostly lived in the side box beams. The 1979 Fittipaldi F6 had tall aluminium honeycomb side panels (and the Wolf WR9 also to a certain extent) and all the fuel behind the driver, but these cars were not succesful (for other reasons). Had they been, I suspect all subsequent cars would have had tall side structural side panels from 1980, but that, of course, is pure speculation. BTW, IIRC Chapman went backwards structurally with the T79 because he found honeycomb sandwich panels too difficult to stress, fabricate, assemble and repair, so it may have been a simple case of Team Lotus' seemingly persistent lack of time AND money...He and Lotus did learn from that mistake relatively quickly, though, (with help from Peter Wright) so, not surprisingly, Lotus had the first deep-sided carbon composite tub ready at the same time as Barnard's pioneering MP4/1...
Come to think of it, I can't OTTOMH remember a driver being killed or seriously injured in a shallow chassis car due to lack of lateral protection above hip height, but there may have been some - perhaps in Lola T330/T332s as there were so many of those in front line action?
I've always been a bit surprised that so few used a triangular section for the box beam longerons - easy to build and with its truss-like cross section it could rely less on closely spaced bulkheads for torsional stiffness relative to a rectangular or other polygon shape, which would have been handy in the days when the fuel bags typically resided there. I also just happen to like the shape visually...
Peter,
Aren't Murray's triangular beam chassis just neat? I wouldn't be surprised if they are impressively stiff, even by modern standards. The Ken Sears/John Surtess TS19/20 was also quite neat and visually pleasing, and probably also very stiff for its generation. Another thing I find very neat is the way that Murray obtained a degree of progressive pullrod-operated springing simply by locating the pivot of the bottom 'tappet' high on the chassis, rather than using a massively complicated 'spider' on the upper wishbone, as on Lotus T72/76, Parnelli VPJ1, Ensign MNo75-77 and Amon AF1 - Murrays method was also used on the Surtess but in a somewhat less elegant manner (although rather I do like Surtees' wide-based lower rear wishbone and upper parallel links).
Anyway, on the subject of suspension members, with wishbones being 'wear items' one wants them to be simple items - on our Formula Fords we let the pullrod pick up directly on the uprights (also at the front), so our wishbones are just tubes and laser-cut lug plates, all of them non-handed (oops - sorry about the shamless plug and thread detour...)
Peter,
it's just great to have somone of your awesome present-day design stature show such deep affection and interest for our sport's history - keep it up!
#54
f1steveuk
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Posted 11 November 2008 - 15:17
Originally posted by Twin Window
Stranger things have been known to happen...
;)
And I posted on there too! There were many legends within FOM and the ex Brabham boys about how BCE pinched the deal from under Hill's nose.
(Goes to prove, you can't type sarcasm, as I had attempted too, I'll get me coat!)
#55
Bonde
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Posted 11 November 2008 - 16:00
David,
In aviation that old adage was/is normally used the other way around, i.e. "what works [flies] right, looks right", simply because there are many cases of that having been true AND many cases of designs that looked right but weren't. Obviously there have also been cases of designs that were less than pretty, or even downright ugly, but actually worked well...say, like just about all F1 cars of the last decade. Still, brutal functionality can have its own aesthetic appeal, so I suppose it just goes to show that beauty is in the eye of the beholder, doesn't it?
Ref a Hill-Alfa deal: Although the GH2 tub does have a faint similarity with that of the BT45, I doubt that the GH2 would have provided adequate fuel volume in the as-built DFV-powered form to satisfy the thirst of the Alfa twelve - remember Murray had to extend the chassis side members all the way back to the rear wheels in order to accommodate enough fuel on both the BT45 and the properly 'triangular' BT46 - luckily, the Alfa was apparently easy on spark plugs...
In aviation that old adage was/is normally used the other way around, i.e. "what works [flies] right, looks right", simply because there are many cases of that having been true AND many cases of designs that looked right but weren't. Obviously there have also been cases of designs that were less than pretty, or even downright ugly, but actually worked well...say, like just about all F1 cars of the last decade. Still, brutal functionality can have its own aesthetic appeal, so I suppose it just goes to show that beauty is in the eye of the beholder, doesn't it?
Ref a Hill-Alfa deal: Although the GH2 tub does have a faint similarity with that of the BT45, I doubt that the GH2 would have provided adequate fuel volume in the as-built DFV-powered form to satisfy the thirst of the Alfa twelve - remember Murray had to extend the chassis side members all the way back to the rear wheels in order to accommodate enough fuel on both the BT45 and the properly 'triangular' BT46 - luckily, the Alfa was apparently easy on spark plugs...
#56
f1steveuk
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Posted 11 November 2008 - 16:25
I'm using my memory, but I'm sure Gordon Murray said the rear "booms" were more for mounting the engine than for fuel , although I concede he also said he had to put fuel everywhere he could as it was so thirsty. No two Alfa flat 12s were the same, and Herbie and the boys still have boxes of "engine mounting" shims. Thinking about it, Bernie might have done Graham a favour!
The T370 Cosworth to Alfa conversion suggested that a lower monocoque could be used, "if" the Alfa deal was signed, and I think Andy Smallman was quite advanced when he was told they didn't have the deal.
The T370 Cosworth to Alfa conversion suggested that a lower monocoque could be used, "if" the Alfa deal was signed, and I think Andy Smallman was quite advanced when he was told they didn't have the deal.
#57
PeterElleray
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Posted 11 November 2008 - 19:57
Bonde - we could talk about this stuff for ever, given half a chance...
the analogy of two beams in differential bending is spot on - infact it was just such an analysis that i had to do over 20 years ago to try and work out why we were building very unstiff carbon chassis at arrows...
i think one of the subtle things about 008 might be in the front suspension - as some here will know, the car was originally designed by MP for an active system, and only redrawn for a conventional system later, before manufacture. in the process it gained a LOWER rocker arm, ie the spring damper is actuated by a rigid cantilever frame integrated into the lower wishbone. it looks like a pushrod but isnt. its the same system as on the Arrows A1 rear UPPER rocker, or indeed the Porsche 956 rear rocker . however, it means that the vertical loads on 008 go into the tub at the floor level - not at the top of the tub. at the top - wher the bif hole is - there is just transverse shear of a relatively low magnitude.
rather than trying to twist the pontoons transversally (ie about a fore -aft axis and through the junction with the floor), as a rocker (Hesketh/Coyote - or Shadow DN8 (another shallow winner)), or outboard coil over damper (Hill, Lola) i think this results more in bending the pontoon about its neutral axis laterally . The section in this plane is much larger - and the lower pivot point is much closer to the car centre than the upper. both would make it inherantly stiffer. does that make sense?
clever chap Maurice Phillippe, we should start a thread about him...
peter
btw the tyrrell roll hoop fabrication is pure 60's Lotus practice to my eye (no surprise)..
the analogy of two beams in differential bending is spot on - infact it was just such an analysis that i had to do over 20 years ago to try and work out why we were building very unstiff carbon chassis at arrows...
i think one of the subtle things about 008 might be in the front suspension - as some here will know, the car was originally designed by MP for an active system, and only redrawn for a conventional system later, before manufacture. in the process it gained a LOWER rocker arm, ie the spring damper is actuated by a rigid cantilever frame integrated into the lower wishbone. it looks like a pushrod but isnt. its the same system as on the Arrows A1 rear UPPER rocker, or indeed the Porsche 956 rear rocker . however, it means that the vertical loads on 008 go into the tub at the floor level - not at the top of the tub. at the top - wher the bif hole is - there is just transverse shear of a relatively low magnitude.
rather than trying to twist the pontoons transversally (ie about a fore -aft axis and through the junction with the floor), as a rocker (Hesketh/Coyote - or Shadow DN8 (another shallow winner)), or outboard coil over damper (Hill, Lola) i think this results more in bending the pontoon about its neutral axis laterally . The section in this plane is much larger - and the lower pivot point is much closer to the car centre than the upper. both would make it inherantly stiffer. does that make sense?
clever chap Maurice Phillippe, we should start a thread about him...
peter
btw the tyrrell roll hoop fabrication is pure 60's Lotus practice to my eye (no surprise)..
#58
David Beard
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Posted 11 November 2008 - 21:18
Originally posted by PeterElleray
clever chap Maurice Phillippe, we should start a thread about him...
I've just bumped an old one..I hope it will serve.
#59
Bonde
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Posted 11 November 2008 - 21:22
I suppose some people would call us nerds (or just anoracs!)...but it definitely is an honour (and a bit intimidating!) for me to engage in such a discussion with someone so superior to me in racing car engineering and design talent - thanks Peter, for taking your time!
Yes, Mr. Philippe was a clever man - sometimes a bit too clever perhaps: The 1972 Indy Parnelli comes to mind, but I do love the shape of that car and the intricately fabricated front subframe carrying the front suspension. You're right, Maurice Philippe does deserve a TNF thread of his own.
Your 008 description certainly makes sense to me. Putting the vertical loads in at the stiffer lower wishbone pick up was clever indeed - the lower wishbone (for those who hadn't thought about that!) is subjected to lateral and longitudinal loads typically 2-3 times greater than the upper one, depending on ratio of vertical distances to the road contact point, so the chassis structure had to be stiffer down there anyway. The compression member acting on the spring also provides compression relief for the lower wishbone, and it all keeps the centre of gravity low. The arrangement requires some very large cutouts in the side though (and at the top for access) in order to accommodate the compression member of that well-triangulated lower rocker. The 008 is a fascinating car though - so different from what came before and what was to follow.
BTW, Ferrari used that tubular truss rocker at the back as early as 1971 on the 312B2 - Arrows, Toleman and Porsche were later incarnations. Of course, Toleman went for it at the front also when they discovered that their shallow box section front rockers weren't stiff enough on the "Belgrano", the added upper trusswork poking unceremoneously into the airstream and through the front bodywork - an afterthought if there ever was one! One is reminded of the trusses added under some VERY old racing car ladder frames and on many railway cars over time...Of course, Rory Byrne would return to greatness later - his Royale RP21 and RP24 were already great designs prior to the Toleman interlude, although the upper front spring/damper unit pick-up point appeared to lack some vertical support on the RP21. Did Byrne design the Toleman TG281 BTW, or was that somebody else's Lola design?
What Arrows was that unstiff one, Peter? (I'm here to learn - mistakes of others are fine, too...)
I can't remember having seen any of Bob Riley's Coyotes or Wildcats without bodywork installed, but I don't think there would have been much room for any bridging structure in the area, but at least the front rocker appears to have been right up against the front bulkhead. And those Riley cars (I assume that it is the Riley of Riley & Scott?) had some wonderfully neat and simple fabriocated front uprights with the upper steering ball at hub centre height. But, as Colonel Capps would say, I digress...
Still on the subject of two parallel beams in differential bending: I've noticed that some cars, even succesful cars such as the 1972 Indy Eagle and the Lola T330/332 F5000, had very little structure joining the aft ends of the two side beams - I suppose they largely relied on the engine to perform that function.
Steve,
You are right - there is an engine attachment at the back end of each of the long chassis side members, certainly on the BT45 and I suspect on the BT46 also - with fuel tankage going right back there, too.
Yes, Mr. Philippe was a clever man - sometimes a bit too clever perhaps: The 1972 Indy Parnelli comes to mind, but I do love the shape of that car and the intricately fabricated front subframe carrying the front suspension. You're right, Maurice Philippe does deserve a TNF thread of his own.
Your 008 description certainly makes sense to me. Putting the vertical loads in at the stiffer lower wishbone pick up was clever indeed - the lower wishbone (for those who hadn't thought about that!) is subjected to lateral and longitudinal loads typically 2-3 times greater than the upper one, depending on ratio of vertical distances to the road contact point, so the chassis structure had to be stiffer down there anyway. The compression member acting on the spring also provides compression relief for the lower wishbone, and it all keeps the centre of gravity low. The arrangement requires some very large cutouts in the side though (and at the top for access) in order to accommodate the compression member of that well-triangulated lower rocker. The 008 is a fascinating car though - so different from what came before and what was to follow.
BTW, Ferrari used that tubular truss rocker at the back as early as 1971 on the 312B2 - Arrows, Toleman and Porsche were later incarnations. Of course, Toleman went for it at the front also when they discovered that their shallow box section front rockers weren't stiff enough on the "Belgrano", the added upper trusswork poking unceremoneously into the airstream and through the front bodywork - an afterthought if there ever was one! One is reminded of the trusses added under some VERY old racing car ladder frames and on many railway cars over time...Of course, Rory Byrne would return to greatness later - his Royale RP21 and RP24 were already great designs prior to the Toleman interlude, although the upper front spring/damper unit pick-up point appeared to lack some vertical support on the RP21. Did Byrne design the Toleman TG281 BTW, or was that somebody else's Lola design?
What Arrows was that unstiff one, Peter? (I'm here to learn - mistakes of others are fine, too...)
I can't remember having seen any of Bob Riley's Coyotes or Wildcats without bodywork installed, but I don't think there would have been much room for any bridging structure in the area, but at least the front rocker appears to have been right up against the front bulkhead. And those Riley cars (I assume that it is the Riley of Riley & Scott?) had some wonderfully neat and simple fabriocated front uprights with the upper steering ball at hub centre height. But, as Colonel Capps would say, I digress...
Still on the subject of two parallel beams in differential bending: I've noticed that some cars, even succesful cars such as the 1972 Indy Eagle and the Lola T330/332 F5000, had very little structure joining the aft ends of the two side beams - I suppose they largely relied on the engine to perform that function.
Steve,
You are right - there is an engine attachment at the back end of each of the long chassis side members, certainly on the BT45 and I suspect on the BT46 also - with fuel tankage going right back there, too.
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#60
PeterElleray
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- 1,120 posts
- Joined: January 04
Member
Posted 11 November 2008 - 22:11
Bonde, stop that or i wont come out to play! i dont think track record, profile, being in the right place at the right time or anything else, like luck, have a bearing on ones understanding of the engineering and the physics we are discussing here. noone would give me the time of day before June 2003 - nothing had changed , except the Bentley's didnt break down like some expected and , remarkably, i found i had lots of new friends...
anyway what we have in common is a fascination for the 70's and the 80's before it all got a bit too 'corporate'.
there were two unstiff arrows, we've discussed the A9 on here before, but the A8 was initially about half as stiff as the A7 (aluminium h/c)...
Maurice is a bit of a hero of mine, he had a role in getting me involved in professional racing, and i knew him quite well in the mid '80's. i think i know his cars well now, i wish i'd known them better when i knew him, i have so much more i didnt ask him..
oh well, i will post on the thread David has revived, as he says there, lets talk about his cars, i see we're in good company...
peter
anyway what we have in common is a fascination for the 70's and the 80's before it all got a bit too 'corporate'.
there were two unstiff arrows, we've discussed the A9 on here before, but the A8 was initially about half as stiff as the A7 (aluminium h/c)...
Maurice is a bit of a hero of mine, he had a role in getting me involved in professional racing, and i knew him quite well in the mid '80's. i think i know his cars well now, i wish i'd known them better when i knew him, i have so much more i didnt ask him..
oh well, i will post on the thread David has revived, as he says there, lets talk about his cars, i see we're in good company...
peter
#61
Bonde
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- 1,072 posts
- Joined: December 04
Member
Posted 11 November 2008 - 22:19
Oh Peter - plllleeeaaassse come out to play! (And there's no need to be so modest - designing Le Mans winners is in most even slightly knowledgable people's book a huge achivement requring massive skill and talent).
On the Arrows business, I suppose I'll just have to bounce the A9-inflicted thread then...
On the Arrows business, I suppose I'll just have to bounce the A9-inflicted thread then...
#62
f1steveuk
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- 3,588 posts
- Joined: June 04
Member
Posted 12 November 2008 - 12:12
I interviewed Peter Warr recently, and he told the story of how he wanted "a lighter, faster 72", and got the 76! Peter then went on to say the Parnelli VPJ4 is what they should have designed. Clever man indeed!
#63
John-w
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- 180 posts
- Joined: August 05
Member
Posted 22 January 2009 - 20:01
Hello,
here are some photos from Iritani’s latest kit, the Hill GH-2 in scale 1/20th. The Iritani kit includes a lot of parts made of resin, metall, plastic and rubber. The instruction manual (20 pages) is very detailed. This kit has 2 assemble options: Original from 1975 and the recently restored.
I am searching photos from the car without the airbox.
John-w
http://www.iritanikits.com/
here are some photos from Iritani’s latest kit, the Hill GH-2 in scale 1/20th. The Iritani kit includes a lot of parts made of resin, metall, plastic and rubber. The instruction manual (20 pages) is very detailed. This kit has 2 assemble options: Original from 1975 and the recently restored.
I am searching photos from the car without the airbox.
John-w
http://www.iritanikits.com/
#64
Peter Morley
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- 2,263 posts
- Joined: October 02
Member
Posted 23 January 2009 - 09:40
You could ask the current owner Klaus if he could send you any photos you need.
http://www.speedyracing.ch/hill21.htm
http://www.speedyracing.ch/hill21.htm
#65
Andre Acker
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- 281 posts
- Joined: August 05
Member
Posted 23 January 2009 - 12:01
The wheels of the restored car do not seem original or similar to those from 1975 / 1976.
On the other hand, we will never know if the car would be competitive, but it is a very beautiful car.
The rear wing is wonderful !
Good times when the cars were different one to the other ...
Changing subject, does anyone has a photo of the Embassy Hill team t-shirt from 1974 / 1975 ?
Many thanks and very best regards.
André Acker.
On the other hand, we will never know if the car would be competitive, but it is a very beautiful car.
The rear wing is wonderful !
Good times when the cars were different one to the other ...
Changing subject, does anyone has a photo of the Embassy Hill team t-shirt from 1974 / 1975 ?
Many thanks and very best regards.
André Acker.
#66
P0wderf1nger
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- 424 posts
- Joined: June 07
Member
Posted 01 February 2009 - 19:17
Originally posted by Jorge Felix
Jorge
Apologies for dragging you back to such an old thread, but this image intrigues me.
Do you if it was taken during Embassy Hill's first visit to Paul Ricard for winter testing, in early November 75, or during the second one later that month, which led to the fatal air accident?
I only ask because I'm writing a book about Amherst Villiers, who had spent the previous months doing some work for the team, and attended that first test. I'm keen to know if there are any photographs of him at that session.
Thanks
Paul
#67
Jorge Felix
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- 107 posts
- Joined: November 00
Member
Posted 02 February 2009 - 14:26
Originally posted by P0wderf1nger
Do you if it was taken during Embassy Hill's first visit to Paul Ricard for winter testing, in early November 75, or during the second one later that month, which led to the fatal air accident?
Paul
Paul
I'm not sure about that. I think I have some more pictures, but have to search for them, which may
take some time... Sorry not to be a great help in your quest.
#68
P0wderf1nger
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- 424 posts
- Joined: June 07
Member
Posted 02 February 2009 - 15:01
Originally posted by Jorge Felix
Paul
I'm not sure about that. I think I have some more pictures, but have to search for them, which may
take some time... Sorry not to be a great help in your quest.
Thanks Jorge, no worries and in your own time, but if you do see a chap in his mid-70s hanging around the Embassy-Hill pits in any of your images, be sure to let me know!
If it's any help, I understand the team's first visit to Paul Ricard, which he attended, was around 7 November. The second, obviously, ended on 29 November, the day Graham Hill, Tony Brise, Andy Smallman, Ray Brimble, Terry Richards and Tony Alcock lost their lives.
By the way, anyone interested in the flight and its disasterous conclusion should google N6645Y, the (non-)registration of Hill's plane. Aircraft Accident Report 14/76 can be downloaded as a pdf.
Rgds
Paul
#69
charles r
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- 8,403 posts
- Joined: January 07
Member
Posted 02 February 2009 - 15:59
A sobering read. 
Originally posted by P0wderf1nger
Thanks Jorge, no worries and in your own time, but if you do see a chap in his mid-70s hanging around the Embassy-Hill pits in any of your images, be sure to let me know!
If it's any help, I understand the team's first visit to Paul Ricard, which he attended, was around 7 November. The second, obviously, ended on 29 November, the day Graham Hill, Tony Brise, Andy Smallman, Ray Brimble, Terry Richards and Tony Alcock lost their lives.
By the way, anyone interested in the flight and its disasterous conclusion should google N6645Y, the (non-)registration of Hill's plane. Aircraft Accident Report 14/76 can be downloaded as a pdf.
Rgds
Paul
#70
John-w
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- 180 posts
- Joined: August 05
Member
Posted 07 February 2009 - 14:35
Hello,
my Hill GH-2 is finished now.
More photos on my homepage:
http://www.john-w.de/models/news.htm
John-w
my Hill GH-2 is finished now.
More photos on my homepage:
http://www.john-w.de/models/news.htm
John-w
#71
colinsays
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- 139 posts
- Joined: July 09
Member
Posted 05 February 2015 - 12:16
I just found it.
I think is quite interesting (specially the tiny Fiat 126) and the mystery sportscar...
#72
Tim Murray
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- 24,607 posts
- Joined: May 02
Moderator
Posted 05 February 2015 - 12:47
The 'mystery sports car' is one of the Ogle-bodied Aston Martin DBS V8 cars, discussed in this earlier thread:
http://forums.autosp...otheby-special/
The thread includes a link to another site with lots of info on the cars.
http://forums.autosp...otheby-special/
The thread includes a link to another site with lots of info on the cars.
#73
alansart
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- 4,420 posts
- Joined: March 07
Member
Posted 05 February 2015 - 16:45
The 'mystery sports car' is one of the Ogle-bodied Aston Martin DBS V8 cars, discussed in this earlier thread:
http://forums.autosp...otheby-special/
The thread includes a link to another site with lots of info on the cars.
Ogle's were built in Letchworth not far from where I lived at the time.
My photo at Silverstone that appears on the other thread: 
#74
ensign14
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- 62,006 posts
- Joined: December 01
Member
Posted 05 February 2015 - 22:29
May as well throw in my three pics...
I took these with a Fuji Finepix, which had (has) 2.1 megapixels. Shows that it's not all about the pure numbers, the images stand up pretty well to big magnification.
