More informative reasons for DNF

[jaydee]

Hey everybody,

I'm writing a paper for a university course exploring hydraulics in F1 and other racing serieses. I've found a lot of good information in Peter Wrights books for instance, but one thing I'm still wondering about are the failures of hydraulic systems in F1. It's an oft blamed reason for a DNF in F1, but I'd be interested in finding more detailed information about these. Loss of pressure, why, etc. Anything pointing me to some direction is much appreciated. Maybe there's a site that has more detailed information about DNF's? Even word of mouth is better than nothing.

- jaydee

[DaveKillens]

Whenever a car retires, it is an embarassment to the team, and all associated. And if a supplier part is responsible for the problem, then it becomes a political problem. Naturally, no team will go on record bashing one of their partners and suppliers. That is whey (hypothetically) a team would never say "Our car had to retire because the part supplied by Company X failed".
Instead, there is a cover story generated, and almost always goes like this. "Our car retired because of hydraulic problems". Or electrical problems. But what is released to the public is always generalized and vague on purpose.
Formula One exists in a climate of secrecy, and no team will willingly divulge anything that may compromise their status, or secrets.

So whenever you come across a statement about technical problems, please remember that most likely it is a cover story, and the real truth is most likely obscured.

[Tim.Wright]

Hydraulics control so much on the cars. From memory, the power steering, gearbox, fuel flap actutor etc. So if the pump fails, or a pressure line leaks you lose your gears and steering effort.

I don't know any better but I would guess the problems would be general problems all hydraulic system may encounter ie Leaking seals, cracked fittings from vibration or even the electrical systems which control the pump may malfunction.

Tim

[safeaschuck]

Dave K, Yep. Damn right. They usually try and avoid listing anything to do with the engine as a cause of D.N.F. becuase this is so closely tied in with the branding/image of the manufacturer (one of the few things they can claim some technology cross over). Gearbox's and hydraulics usually get a bashing but this is rarely accurate. When you see a technical report of a striped down item that allegedly failed causing the D.N.F. and it is either perfectly o.k. or has only failed as a result of some other cataspropic failure in the drivetrain you realise that it's the P.R. people not the engineers that file the info for the casual veiwer. If they have to list engine failure an option it's probably because everyone saw it blow up! Brundle is usualy onto it though. And some of the specialist magazines. When they say a team has reliability issues with the engine you can probably read between the lines of future D.N.F.'s

[pitlaneimmigrant]

It is understandable that teams won't want to go into too much detail about how their systems operate/fail as it could give the opposition an insight into their design. In much the same way that you wouldn't discuss the details of how your gearbox's fancy new shift mechanism failed.

The hydraulic systems control steering, fuel flap, gearshift, clutch, diff and throttle so there are a lot of ways for things to go wrong if the hydraulics nip up. The systems are also highly tuned, the moog valves used are aerospace spec but are even lighter than standard. The valves are essentially made to order with a typical 4 port valve costing about 2-3000 pounds!
However, when you're measuring gearshifts in milliseconds and clutch displacements in microns that is what is required.

Also hydraulics are an easy thing to blame without making anyone look bad. It's like the old story that any Honda DNF was due to electrical problem because it was unacceptable to admit an engine failure (the fact that the electrical problem was caused by a conrod chopping the loom in half was irrelevant!)

Back on topic, you're unlikely to find detailed info on reasons for DNFs as this could potentially give away design info. Also repeat failures are very unusual in F1 as the problem solving process is very thorough. F1 cars are essentially prototypes so failures will happen, but in a team with good fault diagnosis, testing and reliability the same failure is very unlikely to happen twice

[riff_raff]

DaveKillens got it right.

"hydraulic failure" is just a code phrase for "We don't want to disclose the real problem because it might embarrass one of our sponsors that gives us millions of dollars".

Seriously, designing a reliable hydraulic system is not rocket science. The brake system on your road car is a (simple) hydraulic system. And if it has ABS function, it's a very complex, high-frequency, electronically modulated hydraulic system. Your car's power steering is also a hydraulic system. How often do either one of those systems fail on you?

With the financial resources available to most F1 teams, they should be able to design a reliable race car, hydraulic systems included. Back when I worked for a race team, most of the mechanical DNF's we had were due to mistakes made during the chassis or engine build and prep. It was easy for the mechanics to make mistakes because they were always in a hurry during a race weekend.