Red Bull RB18

[AR3-GP]

The regs though stipulate that steering angle mustn't correlate to excessive changes in ride height. I don't know if the FIA inspects that with the car stationary, or if they review geometry directly, or request CAD data.

The regs say that a "POU" like action, cannot be activated by steering angle. It doesn't say anything about activating this POU like behaviour through braking forces (which could never arise in any static test).

However, the Ferrari seemed to be much better on the brakes in Australia.

[vorticism]

Right, that's why I ask how the FIA inspects this rule. If it's a static test they might have figured out a way to replicate the effect at speed. If it's a geometrical/digital inspection then it would reveal itself. Interesting idea though. Wheel upright torque deflects the longbow, changing the caster and camber, although I'm not sure if that would alter the pullrod characteristics much. I'd think this would show up in the onboards somewhat, though.

Edit- As for the rear suspension, if the lower element is connected through the corner springs, if it simply had a restrictive valving to lower the bound/rebound rates, then it should be able to hold a certain ride height beyond a threshold of wheel travel, by making the displacement of the far end of the corner springs slow to react. It is unusual looking in how narrow and simplistic it looks, compared to the topside elements. This is all conjecture, it's unclear if there are corner springs and if so how they are mounted. If they are attached at the ends, then this means they have no ground to chassis. They could only act as a heave element.

[SSScoffee]

[Wouter]

From his source:

Helmut Marko : "The problems we had in Bahrain were different from the problems we had in Australia and also different from the problems we had in winter testing. But according to Honda, we can count on the problems to be resolved before the next race."

And what about Verstappen's engine with which he retired in Melbourne? After all, there seemed to be flames coming from under the hood? That is the second good news for Verstappen:
"Everything is fine with that. The problem was not in the engine itself, but in the fuel line, which burst under high pressure. And we think that had to do with the problem of porpoising."

Porpoising??

"We do have good control of porpoising, but there are still small movements, mainly due to the way the car 'landed' again. We believe this was the main cause of the damage to the fuel line."

So they have to make sure that the car lands in a different way??? What does that mean and how will they do that?

A few days ago, Marko talked about a "complex" problem. I don't follow it anymore.

[pierrre]

Also, I'm getting confused between Craig's drawing and the actual RB rear end. The detail at the bottom looks completely different:

what he drew probably is based on the Alphatauri AT03 rear suspension

[ringo]

From his source:

Helmut Marko : "The problems we had in Bahrain were different from the problems we had in Australia and also different from the problems we had in winter testing. But according to Honda, we can count on the problems to be resolved before the next race."

And what about Verstappen's engine with which he retired in Melbourne? After all, there seemed to be flames coming from under the hood? That is the second good news for Verstappen:
"Everything is fine with that. The problem was not in the engine itself, but in the fuel line, which burst under high pressure. And we think that had to do with the problem of porpoising."

Porpoising??

"We do have good control of porpoising, but there are still small movements, mainly due to the way the car 'landed' again. We believe this was the main cause of the damage to the fuel line."

So they have to make sure that the car lands in a different way??? What does that mean and how will they do that?

A few days ago, Marko talked about a "complex" problem. I don't follow it anymore.

Packaging maybe is too tight under this car. Something was chafing with that fuel line or the line is using an end connection that is not designed to take too much external loads while under the high pressure. The porpoising can cause the connection to lose seal. So redbull may have to revise its joints, maybe using stronger but heavier couplings.

[AR3-GP]

From his source:

Helmut Marko : "The problems we had in Bahrain were different from the problems we had in Australia and also different from the problems we had in winter testing. But according to Honda, we can count on the problems to be resolved before the next race."

And what about Verstappen's engine with which he retired in Melbourne? After all, there seemed to be flames coming from under the hood? That is the second good news for Verstappen:
"Everything is fine with that. The problem was not in the engine itself, but in the fuel line, which burst under high pressure. And we think that had to do with the problem of porpoising."

Porpoising??

"We do have good control of porpoising, but there are still small movements, mainly due to the way the car 'landed' again. We believe this was the main cause of the damage to the fuel line."

So they have to make sure that the car lands in a different way??? What does that mean and how will they do that?

A few days ago, Marko talked about a "complex" problem. I don't follow it anymore.

A pressure rated fuel line "bursting" without any sign of it being impaled is a complex problem. It shouldn't have bursted under the pressure of the fuel system. That's what's mystfying. The fact that they are guessing that it was porpoising shows they don't for certain what it was. Hence the complexity.

[vorticism]

As far as I've ever seen, the high pressure lines are rigid tubing linking the pump to the fuel rails; typical for DI. These shouldn't be sensitive to low Hz vertical accelerations themselves; it could be that some other factor led to fuel vaporizing which then cascaded to a pump issue which led to a pressure spike damaging a line. If he means relatively high pressure as opposed to high in an absolute sense, then this might be a reference to the flexible hoses on the low pressure side; again suffering a fuel abnormality. Low Hz friction from porpoising acceleration I would not expect to damage a hose, and surely they are routed far away from any exhaust heat. Otherwise he's throwing chaffe as teams will be inclined to do.

Also, I'm getting confused between Craig's drawing and the actual RB rear end. The detail at the bottom looks completely different:

Craig is making the same assessment as Stu. However, if the torsion bars terminate as a pivot, they no longer act as corner springs, but as a component of the heave device. No anchor to chassis. We'd have to consider why. F.e. corner spring rate vs proposed function of this linking device. It also has a miniscule amount of travel as evidenced by the displacement sensor. Otherwise it's just an extension of the rocker without flexibilty.

[AR3-GP]

As far as I've ever seen, the high pressure lines are rigid tubing linking the pump to the fuel rails; typical for DI. These shouldn't be sensitive to low Hz vertical accelerations themselves; it could be that some other factor led to fuel vaporizing which then cascaded to a pump issue which led to a pressure spike damaging a line. If he means relatively high pressure as opposed to high in an absolute sense, then this might be a reference to the flexible hoses on the low pressure side; again suffering a fuel abnormality. Low Hz friction from porpoising acceleration I would not expect to damage a hose, and surely they are routed far away from any exhaust heat. Otherwise he's throwing chaffe as teams will be inclined to do.

This discussion in of itself underlines the complexity of the issue they believe they have. The belief that somehow porpoising could cause fuel line failure. Try working that one out. Complex.

[mzso]

A pressure rated fuel line "bursting" without any sign of it being impaled is a complex problem.

If it would have bursted there would have been a lot more fire.

[dialtone]

There is always option B: Marko is not correct and it has nothing to do with porpoising.

[pierrre]

From his source:

Helmut Marko : "The problems we had in Bahrain were different from the problems we had in Australia and also different from the problems we had in winter testing. But according to Honda, we can count on the problems to be resolved before the next race."

And what about Verstappen's engine with which he retired in Melbourne? After all, there seemed to be flames coming from under the hood? That is the second good news for Verstappen:
"Everything is fine with that. The problem was not in the engine itself, but in the fuel line, which burst under high pressure. And we think that had to do with the problem of porpoising."

Porpoising??

"We do have good control of porpoising, but there are still small movements, mainly due to the way the car 'landed' again. We believe this was the main cause of the damage to the fuel line."

So they have to make sure that the car lands in a different way??? What does that mean and how will they do that?

A few days ago, Marko talked about a "complex" problem. I don't follow it anymore.

one fundermental flaw with what Marko says is that the RB18 does not suffer from porpoising or it does not do it as bad as the other cars. very strange claim which could lead to suspicion

[Zynerji]

I remember Coulthard retiring numerous times in early RBR cars because of solid hydraulic lines bursting. He told the press that flex hoses are heavier, but at least he'd finish the race.

I wonder if this is a similar problem now with solid fuel lines?

[saviour stivala]

In Coulthard’s time at RBR if an RBR car puts as much as a wheel off the tarmac the car used to just disintegrate with parts of the car littering the area.

[pierrre]

Also, I'm getting confused between Craig's drawing and the actual RB rear end. The detail at the bottom looks completely different:

Craig is making the same assessment as Stu. However, if the torsion bars terminate as a pivot, they no longer act as corner springs, but as a component of the heave device. No anchor to chassis. We'd have to consider why. F.e. corner spring rate vs proposed function of this linking device. It also has a miniscule amount of travel as evidenced by the displacement sensor. Otherwise it's just an extension of the rocker without flexibilty.

my suspicion is that the sensor is for data log in into their computer when an adjusment is made to the ride height. the kinematics would immediately be synchronized into their computer system with every adjustments...it makes it so much easier too. data gathering for heave may be done in more sensitive areas within the suspension especially on the heave damper. they usually have one there