75 replies to this topic

[lil'chris]

Originally posted by Tony Matthews

Was the 78 the chassis that was meant to use the 'queer box'?

Was that the Getrag box ?

From memory I think it was for the 79 and Ronnie spent a lot of the first day at many of the 1978 meetings testing it with a view to it eventually being raced, which I don't think happened .

Chris

[Tony Matthews]

[QUOTE]Originally posted by Bonde
[B] I believe aluminium sandwich panels with polyurethane foam cores became quite popular in the early days of 'deformable structure' chassis, and that Coppuck's underrated M26 used aluminium/aluminium honeycomb sandwich structure extensively for main chassis panels, predating the T78 lotus by a couple of years.

Somewhere, Anders, I have photos of the M26 chassis, but can't lay my hands on them quickly. Also, didn't the M26 have an early attempt at under-car air management with kevlar skirts that formed a triangle , the apex somewhere about the front wheel centre-line and meeting the outer edges of the side-pods farther back?

[Tony Matthews]

Originally posted by lil'chris


Was that the Getrag box ?

From memory I think it was for the 79 and Ronnie spent a lot of the first day at many of the 1978 meetings testing it with a view to it eventually being raced, which I don't think happened .

Chris

Yes, on reflection I think it was the 79. I have vivid but disjointed memories, and they are not necesssarily in chronological order!

My memory is that it was not the Getrag box, unless the castings were used to house Lotus internals, but it certainly didn't work!

[Bonde]

Lil'Chris and Tony,

I must've been editing my post (#49) while you were typing...Getriebe Aktiengesellschaft and T79 'twas indeed!

Tony,

I don't ever recall seeing the underside of M26, but it certainly sported some very visible Kevlar (my assumption is based on the brownish-tan colour) skirts along the edge of the tub, as did M23, beginning in 1976, IIRC.

Peter - Thanks - something to look forward to!

Signing off...

[fines]

The M26 certainly suffered from following up the iconic M23, and a few development problems in '76. In my opinion, it was a very nice and quite effective weapon in the hands of James Hunt, at least. Shame it was made obsolete so soon!

[PeterElleray]

Originally posted by fines
The M26 certainly suffered from following up the iconic M23, and a few development problems in '76. In my opinion, it was a very nice and quite effective weapon in the hands of James Hunt, at least. Shame it was made obsolete so soon!

Gordon (Coppuck) did some really nice cars in that period. when he worked for arrows as a consultant i asked him about that era, he was very modest about everything, going so far as describing the M28 as 'not a good car' - quite a difficult thing to admit to a young engineer you dont really know that well. i respected him a lot for that. i always thought that he did a prety effective job of resoring his reputation (which did take a knock with the M28) with the Spirirt F2 car - notwistanding the fact the M29 and M30 came in between. i suspect there was a lot more shop floor design going on at McLaren at that time and that those cars didnt necessarily reflect Gordon's ideas or wishes - for me, the Spirit is where the designer of the honeycomb M26 would have gone next...

Peter

[Bonde]

...and interestingly enough, that beautiful honeycomb Spirit tub carried Honda back into F1 in 83...

With the M28 McLaren got a bit too clever for their own good. My first thought on seing it launched was "How on earth are they going to get that thing around corners?" It just looked so huge, and apparently the chassis, although mostly honeycomb, was too flexible. I've never seen many photos of the M28 laid bare, so I can't really comment on what caused that flexibility, although a very long wheelbase does place extra premium on rigidity, and unlike the Lotus T78, the side beams stopped at waist height which certainly costs a lot of stiffness, all else being equal.

I remember seing in the lamented Grand Prix International (this was back when technical details and close-up photos of current machinery was normal) an article comparing the M29 and M30 chassis - IIRC, the M30 had two largish box-section torsion beams running the length of the chassis at waist height, free of the tunnel floor, whereas the M29 didn't, which seems to indicate M30 was born in part to address a chassis stiffnes inadequacy on the M29. I've always been puzzled how Coppuck and/or McLaren could get it so wrong in the early years of ground effects, considering their common pedigree. Coppuck had also designed the neat and robust M15 and the gorgeous trend-setting M16 USAC Indy cars, lest we forget, but as Peter says, "the other Gordon" certainly made ammends with that brilliant F2 Spirit.

[PeterElleray]

Originally posted by Bonde
...and interestingly enough, that beautiful honeycomb Spirit tub carried Honda back into F1 in 83...

I've never seen many photos of the M28 laid bare, so I can't really comment on what caused that flexibility, although a very long wheelbase does place extra premium on rigidity, and unlike the Lotus T78, the side beams stopped at waist height which certainly costs a lot of stiffness, all else being equal.

I

i think the honeycomb panels delaminated themselves.. or maybe under initial loading. whether this was a design problem or manufacturing i dont know. also dont know but seem to vaguely remember that some inserts may have pulled aswell.

stacks up with finishing well up in argentina and then falling off the pace.

Anders - check your PM !

Peter

[Bonde]

Peter,

The devil is in the details, isn't it? Still a bit strange, since Cuppock would have had quite a lot a lot of experience with honeycomb by then...

(PM checked and responded to)

[Engineguy]

Originally posted by Bonde

I've often wondered how they wired those cutout edges on the scuttle panel of the T79 without overstraining the material. What temper was the L72 in? (And I'm trying to remember what the AA-designated alloy/temper equivalent would be).

Per NASA:

L72: 2014 T4
L73: 2014 T6
.

[IrishMariner]

Originally posted by Tony Matthews
...Perhaps I should start a thread devoted to the craftsmen responsible for creating these fascinating machines...

Yes Please.

Really must say - I'm loving these pictures and sketches you are posting in various threads, sir.

[Gary Jarlson]

Earlier in this thread Peter wrote:

"one final point - if the FISA had stamped down on sliding, as opposed to flexible skirts , as many belived they ought to have done from the start - the old argument about moving aerodynamic devices - what sort of an advance would the Lotus 79 have represented over the 78? "

I seem to recall that in a contemporary race report on Anderstorp (Autocourse? Competition Press?), Eccelstone said the real intent of the Brabham fan car--beyond any obvious performance gain--was to force the FIA/CSI into clarifying once and for all where the sliding skirts fell in the category of moveable aerodynamic devices. We all know that Brabham agreed not to run the car again, but I can't imagine Bernie's agreeing to this without something substantial in return.

I can't believe that I've imagined this scenario.

[ghinzani]

What was the last non ground effect car in F1 in the ground effect era - the flat 12 Brabham perhaps in early 79? Or the Ensigns I guess? Didnt they revert to the flat bottom car for a bit when the 'wing car' plutzed?

[COUGAR508]

Originally posted by fines
The M26 certainly suffered from following up the iconic M23, and a few development problems in '76. In my opinion, it was a very nice and quite effective weapon in the hands of James Hunt, at least. Shame it was made obsolete so soon!

Yes, just when they appeared to have ironed out the bugs and gremlins with the M26, others were already making great leaps forward, and planning even greater advances.

[Charles E Taylor]

The Lotus Getrag "queerbox"



The 'queerbox' development was interesting, as was differential technology development - the late seventies/early eighties weren't all about aerodynamics, turbocharging and structural materials and methods. Nowadays we take sequential 'boxes for granted, but had someone succesfully introduced a push-pull cable-operated one sooner, the advent of the paddle-controlled electromechanical/pneumatic 'box might have been delayed a bit - after all, a cable (albeit quite stiff) is easier to fit in and sequetial doesn't need lateral shifter movement, something that was growing as 6, and perhaps eventually 7, gears were coming in.

------------------------------------------------------------------------------------------------------

The 70’s were indeed very interesting times. A time before thought and creativity was strangled by money and regulation.

The Lotus Getrag gearbox project started alongside development of the lotus 78. An interesting design with shaft engaged gears, much like a contemporary motorcycle. It had sequential shift. On one box this was altered to H pattern for Andretti.

An early version of this gearbox had a “sprag clutch” free-wheel feature. IIRC this was never tested on the track. The pinion and layshaft was very short (compared with the Hewland FG400) and could accommodate up to 7 gears.

The Gearbox was not a success, it was somewhat under specified for the application. Arthur Birchall the lotus gearbox specialist had a nightmare trying to keep this unit race-worthy.

After many tests and practice sessions particularly with Ronnie driving the only time it was raced was at the Silverstone International Trophy on the first type 79 where Andretti retired.

The type 79 was modified after this meeting to accept the Hewland, which was first run at Monaco . After that the Getrag project was abandoned.




Charlie

[Doug Nye]

Had ground effect never happened...Didier Pironi might have become a Ferrari-borne World Champion...

DCN

[David M. Kane]

Great stuff!

[ghinzani]

Originally posted by Doug Nye
Had ground effect never happened...Didier Pironi might have become a Ferrari-borne World Champion...

DCN

Is that because the ground effect cars threw up more water from the track?

[Paolo]

Sober, if somewhat cynical...

I will try to put soemthing together on the BLAT car tomorrow - i have the eagle book published a couple of years ago which is good on this car, saves me digging into autosport.

Many tomorrows after... I stumbled on this thread looking for info on BLAT.

There seems to be nothing on the net about how it worked, so if someone has printed info, help would be truly appreciated.

In the while, I'll try guessing at how it could have worked: I doubt BLAT cars were "box cars" just propagating the rear wake pressure to a sealed underside.
Wake pressure is only slightly lower than ambient pressure and this system would have been not efficient enough to fight against Venturi cars as the Eagles did.

So I think they used vortexes. It is known that at some ramp angles strong vortexes are generated. This is the reason why Fastback bodies need to be inclined under 20 degrees , or it becomes better to have an hatchback instead.

Vortexes have low pressure inside; of course they also come with a drag penalty, but this could have been a viable system. This is backed also by some people calling BLAT cars "Vortex cars".

So my bet is on a sort of flat bottom F1 car with long diffusers.

Eagle's triangular top view shape could have helped in vortex formation.

Still, BLAT means "boundary layer adhesion technology" and I cannot see the role of boundary layer adhesion in this, unless it refers to some critical angle just before flow separation.

Those are speculations, of course.... any real info out there?

[rallen]

Brilliant thread guys, exactly why I come to TNF! I was wondering though if anyone has any imput into how Lotus could become so bad in 1979 - don't really understand what happened there.

Anyway keep up the good work!

[arttidesco]

Had ground effect never happened...Didier Pironi might have become a Ferrari-borne World Champion...

DCN

But then again if ground effect had never happened the #27 of GV might have piped Didier to the WDC first in 1981 and then again in 1982

[Paolo]

" I was wondering though if anyone has any imput into how Lotus could become so bad in 1979 - don't really understand what happened there. "



Lack of chassis stiffness.
In 1978 the Lotus 79 was the only car with proper ground effect.
By 1979 everybody had it, and the car shortcomings became apparent.

Edited by Paolo, 07 February 2011 - 14:45.

[Charles E Taylor]

Lotus 1979


There were many, many reasons for the demise of Lotus in 1979. Some of these reasons have their foundation in the accident that befell Ronnie at Monza, some more were due to the success of the T79 others we due to external influences like DeLorean and Theim, all in all it became a nightmare from which Team Lotus and Colin Chapman personally never recovered.

In general nobody then knew the potential power of ground effects.

Some of the particular failings were because the team lost a lot of experienced personnel after Ronnie’s accident. New working practices were demanded by Chapman and there was a great deal of dispute. Some of this is outlined in Jabby Crombac’s book.

The T80 used the T79 chassis and this was not a good decision. The chassis was a very crude attempt at a very narrow structure and it took Patrick Head to show Lotus what they should have done.

The aerodynamics of the T80 were seriously compromised by the coke-bottle skirts sticking which led to terminal porpoising , the original Titainium suspension did not help and the car was seriously overweight. The gearbox with a very small cross section had inadequate stiffness which did not help either.

In trying to do too much with too little resource reliability suffered. In summary the season was a great disappointment.

Chapman personally had his hands full of Delorean, David Theim of Essex and others. His priorities were not what they were in 78.

There is a lot more detail, I could go on forev............


All in all, a testament of how not to follow up a dominant season.



Charlie

[rallen]

Wow thanks guys, really appreicate that - is there any books you can recomend for further reading, would love to know more about it.

Back to the original topic - generally do people think ground effect was a good thing for the sport or a bad thing?

[Paolo]

Wow thanks guys, really appreicate that - is there any books you can recomend for further reading, would love to know more about it.

Back to the original topic - generally do people think ground effect was a good thing for the sport or a bad thing?

1) "Theme Lotus" by Doug Nye

2) Anything making the cars stick to the ground more is a bad thing... but I personally became interested in F1 because of the misteries of Venturis. And it was Gilles' era...

[E1pix]

Wow thanks guys, really appreicate that - is there any books you can recomend for further reading, would love to know more about it.

Back to the original topic - generally do people think ground effect was a good thing for the sport or a bad thing?

My vote is bad thing for racing, and drivers, killing Gordon Smiley and likely others.

For F1, I think allowing turbos was even worse for the sport. (I can't believe they're going to screw up the best rules package in over 30 years — whether one likes the cars' looks or not — to go back to turbos.)