The WIP Secret – 4x increase in throughput with one simple change

Why read when you can watch on video?  Click here – 5 mins, with captions.

You can increase the throughput of your show hugely with one simple change.

For real life.

But don’t take my word for it, let’s turn to one of the total gurus – Eli Goldratt. 

As part of the brilliant Goldratt Satellite Program, which you can still buy and watch the legend himself (I’m not associated with it BTW), he tells the story about the maintenance area of the Israeli Air Force.

(You can watch this part yourself right here, about a 10 minute clip.)

How to Maintain an F-16

Here’s the deal – from time-to-time,  F-16 jets would be brought in for a full overhaul, involving pulling them apart, putting them back together.  Mechanics would do this following the book, but from time-to-time they would hit things that the book couldn’t solve.

When this occurred, they would lodge a ticket with the Engineering group – 70-odd experts in jets, who would work out a solution, meet the mechanic at the plane, explain and supervise the fix, then sign-off that it was done.

The life of an Engineer was busy – by the time they got around to a given ticket and worked out the solution, the mechanic would be elsewhere, so to stay useful, the Engineer would work on another ticket rather than stand around. 

And another.

And another.

Which is what decent people do – “if you’ve got time to lean, you’ve got time to clean”.  So don’t lean.

4.5x better?

Now to the data – the average lead time – the time from mechanic initiating job to engineer signing-off complete – was 135 days.  And as this was the thing that determined how many mechanically sound planes could be returned to the air – it mattered.

To get it down, they tried unlimited overtime (that hit physical limits of the people) and no cap on hiring (can’t find enough qualified specialist engineers) …no impact.

Then they made one simple change, that saw lead-time drop over 5 months from 135 days to 30.

Yep, a 4.5x improvement in average time from job initiation to completion.

The Change

And that change – each Engineer was only given three tickets to work on at any time.

That’s it.

Seriously!

That’s it.

What did this do?

When an engineer couldn’t find the mechanic to implement the solution…they would go to their second job.  If that didn’t work…their third.  And if that didn’t work….they could only now go back to the first and…

WAIT!

Yes, just wait.

When the mechanic appeared, they would do the solution, the engineer would explain, supervise and sign-off and it was done.

But Why?

Why did this make such a big difference?

It changed the focus from utilisation of the resource (the engineer) to throughput of the whole system.  To actually shipping things, which in this case was to ship an aircraft that was maintained. 

When seen in this light, an idle engineer waiting for a mechanic was fine.  It was the best thing they could do for the system’s throughput at that point in time.

And…crucially…for each engineer it reduced the number of jobs on their desk from 50 to 3.  Which meant that the set-up time to go from one job to another was slashed.

In a factory, set-up time means changing a machine from one type of production to another.  For people, it means the mental and emotional switching costs of having to go from one thing to another.  There have been numerous studies of the cost of multi-tasking, all of which say “it’s so much more than you think, you don’t want to believe it”.

Slashing set-up costs not only allowed the engineers to do their work more quickly and deeply on each solution, by including this with ensuring that each solution would remained focused on until it was implemented…. the effect on throughput was massive.

And…for each engineer, it meant more of their time thinking and working on actual engineering…and less of their time chasing multiple balls in the air and trying to simply get organised.

Bringing it Home

As Goldratt points out, sometimes this needs to be done with brute force.  Literally make sure there is no way the engineers can start work on more than three tasks.  Draw some sort of hard line.

But the results are remarkable.  And have been repeated in thousands of shops from production to engineering, to design, to development. 

And the same works for your individual tasks as well. For real!

It’s so simple that it’s hard to believe.  Which is why it often doesn’t happen.

You’re mad not to.

Now, over to you.