Stratosphere chamber

 

While at Brooklands, I visited the stratosphere chamber. As an engineer I was fascinated by it. And the expense and trust in the engineer that allowed that expense. I’d like to write a piece for LinkedIn about the stratosphere chamber the engineering behind it;

• the safety requirements needed for it; there was a large bank of CO2 cylinders for fire extinguishing as there is methanol and vulcanised rubber involved

• What it was for what was tested in it

• How the atmosphere inside was achieved and sealed

Id also like to comment on the process of funding, funding approval and gaining trust to spend such a huge amount of money on such a huge project.

Could you help me with a piece that summarises the stratosphere chamber, It’s engineering, its health and safety aspects and the relationship between engineers, the people funding the work and how that might have changed since Barnes Wallace‘s days.

Absolutely. I think there is a very good LinkedIn piece here because the chamber gives you a way into a much bigger engineering question: what does it take for an organisation to trust engineers enough to build something that has never existed before?

One small factual point I would handle carefully: the sources I can find confirm the methanol refrigeration system and the CO₂ fire-suppression installation, but I haven't found a reliable source specifically confirming the vulcanised-rubber aspect. If that was explained to you at Brooklands, I'd include it as something you observed/heard on the visit rather than present it as independently verified fact.

The chamber was enormous: about 25 ft (7.6 m) in diameter and 50 ft (15.2 m) long, with a working volume of roughly 40,000 cubic feet. It could reproduce pressures equivalent to about 70,000 ft altitude, down to roughly one-twentieth of sea-level air density, and temperatures from about –65°C to above +55°C. 

The engineering is particularly lovely. Vacuum pumps removed air to reproduce altitude; refrigeration plant circulated very cold methanol through heat exchangers to cool the chamber; and the huge door ran on rails to close the chamber around the test article. 

And the thing wasn't simply an aircraft-testing box. It was used for pressure-cabin testing on aircraft including the Vanguard, VC10 and Viscount, as well as complete aircraft such as the Scimitar and Sea Vixen. It was also used for things as unexpected as naval guns, diesel machinery, electrical equipment, fishing-vessel models and Arctic clothing. 

That gives you a nice engineering theme: designing the facility was itself a major engineering project before the actual engineering work could even begin.

What does it take to trust an engineer?

I visited the Barnes Wallis Stratosphere Chamber at Brooklands this week.

As an engineer, I found myself almost more fascinated by the facility than by the aircraft it was built to test.

Built in the late 1940s for Vickers, the chamber was designed to reproduce the extraordinary conditions an aircraft might encounter at very high altitude.

Think about what that means.

A chamber roughly 25 feet in diameter and 50 feet long.

Air pressure reduced to around one-twentieth of sea-level conditions — equivalent to an altitude of around 70,000 feet.

Temperatures ranging from around +55°C down to –65°C.

And enough space to test substantial aircraft structures and even complete aircraft.

The engineering required to make that possible is extraordinary.

Vacuum pumps extracted the air to reproduce altitude. A huge refrigeration system circulated extremely cold methanol through heat exchangers to bring the temperature down. A massive door, running on rails, sealed the chamber so that the environment inside could be controlled.

And then there was the safety engineering.

The refrigeration system involved flammable materials, including methanol, and the facility had a substantial bank of CO₂ cylinders for fire suppression.

This is something I think we sometimes forget when we look at historic engineering projects.

The thing being designed isn't just the thing you can see.

Behind the aircraft test was another enormous engineering system: containment, refrigeration, vacuum, sealing, instrumentation, access, emergency systems and fire protection.

And behind that was something even more interesting.

Trust.

Someone had to decide that this was worth building.

Someone had to approve the money.

Someone had to believe that Barnes Wallis and his team knew enough to justify investing in a facility of extraordinary scale to investigate problems whose answers were not yet known.

That is a very different proposition from funding a project where the business case, technology and outcome are already well understood.

Wallis was effectively asking Vickers to invest in the capability to discover things.

And that is an important distinction.

The chamber wasn't simply built to prove that an existing design worked.

It created an environment in which engineers could find out what happened when they pushed a design into conditions nobody could safely reproduce in ordinary flight testing.

The results could influence aircraft structures, pressure cabins, high-speed flight and ultimately the development of the technology that took aviation towards the supersonic age.

There is something wonderfully bold about that.

But I also wonder how different the conversation would be today.

How would we get a project of this scale through the modern business-case process?

How many gateways would it pass through?

How many quantified benefits would we need to demonstrate before committing the capital?

How would we value the benefit of discovering something that we don't yet know we don't know?

Modern engineering quite rightly places enormous emphasis on safety, assurance, governance and value for money.

But perhaps there is another ingredient we need to protect:

the willingness to invest in engineering capability before we know exactly what it will deliver.

The Stratosphere Chamber reminds me that great engineering isn't only about designing the solution.

Sometimes it is about having enough confidence in engineers to fund the facility that allows them to discover the solution.

And perhaps that is one of the biggest differences between engineering then and engineering now.

Not that engineers were more capable.

But that someone was prepared to say:

"We don't know exactly what we're going to find. Build it anyway."

That's quite a thing to put in a business case.

#Engineering #Innovation #Leadership #CapitalProjects #EngineeringHistory #Brooklands #BarnesWallis #SafetyEngineering