Sauber questions value of F1 in-season testing ahead of 2017 changes

Sauber confirmed last week it would not be taking part in the two-day run at Silverstone, which starts today, due to what it described as "cost effectiveness".

The Swiss team missed the other test at Barcelona in mid-May due to the fact it had no car update for the Spanish Grand Prix, nor a young/test driver that fulfilled the requirements.

On this occasion, although Sauber is closing in on a solution for its financial difficulties, Kaltenborn concedes even if a new investor was already on board, the decision regarding this week would have been the same.

"That's got nothing to do with us not taking part in the test," Kaltenborn told Autosport.

"In any business, unless you get subsidies for it, you look at what it costs you and what the benefits are.

"I just wonder what this test is going to get you in terms of next year [when there is a significant regulation change].

"I'm not finding reasons not to be there, I'm just looking at our situation.

"I see what we have in the pipeline, I know what the costs are, and I make the call.

"I wouldn't do it differently if we had more funding, because you have to see what's coming and where we are.

"If we're delayed on that, it makes no sense to test."

Sauber tested a new rear wing in practice ahead of the British Grand Prix "to collect some data", according to Kaltenborn, and with the hope now to run it at the next race in Hungary.

Other parts have been delayed due to the team's financial struggles, but should become available once the situation has been resolved.

"It's not only things financially - for me it's just how you run your business," added Kaltenborn.

"We have a few things coming and we're confident they will work because in the past we have done it like this.

"We don't have more, and any other decision would be a careless one."