We spoke at YOW this year on the topic of innovation and agile over 6 decades, highlighting the Agile and Lean principles we see in space and engineering projects. From the 1930s we talked about the Cabinet War rooms and that deserves a whole post of its own as we continue to expand our understanding of how physical spaces enable and impact the people and results. From the 1940s we talked about Lockheed Martin and their Skunkworks which we’ve written about before. From the 1950s we looked at some of the magnificent engineering created by that same Skunkworks team… The Agile movement may only be 10 years old, but the principles and the evidence that it works goes back way further than that. We’ll write more reflections on YOW itself at some point, but today you get one of the lessons that most appeals to us.

The U-2 Spy Plane

When the U-2 first flew in 1955, it was an accident. A high speed taxi test saw it rolling down the runway at 70 knots at which point its sailplane wing generated enough lift and it took off into the air unexpectedly. At the other extreme, its cruising altitude of 70,000 feet is referred to by pilots as coffin corner; at this height its stall speed is a mere 10 knots slower than its maximum speed.

The balance is so critical on the U-2 that the cameras had to use a split film setup with reels on one side feeding forward while those on the other side feed backward, thus maintaining a balanced weight distribution through the whole flight.

The plane is incredibly difficult to land because of the lift cushion under the wing as it comes close to the ground. It lands on two inline ‘bicycle wheels’ and the wing tips also land and skid on the ground on titanium plates.

Perhaps the most amazing U-2 fact, and the reason we consider it such a testament to great engineering, is that it’s still in active service today.

The SR-71 Blackbird

This is the fastest and highest flying air-breathing aircraft ever made (only rockets can go higher or faster). It has a maximum speed unspecified above Mach 3.5 (3.5 times the speed of sound) and a maximum altitude also unspecified but in excess of 85,000 feet. At Mach 3.5 you’re covering 1km per second and the engines are sucking in 3 million litres of air every second – an average human breaths in that much air in a year.

The construction of the plane is pretty special too, with 90% of it being made from titanium. At Mach 3+ the surface of the plane heats up to 500+ degrees. The wet patches you can see on the wings and central spine in this photograph are caused by the fuel leaking out of the expansion joint ‘gills’ in the plane. Until about Mach 2.5 when the plane heats up and expands, the SR-71 leaks fuel constantly.

While the Concord can do the transatlantic London to New York flight in about three and half hours, the SR-71 is the way to go if you’re in a hurry. It holds the record at just 1 hour 54 min.

My favourite SR-71 story comes from a pilot in the book Sled Driver: “One day, high above Arizona , we were monitoring the radio traffic of all the mortal airplanes below us. First, a Cessna pilot asked the air traffic controllers to check his ground speed. ‘Ninety knots,’ ATC replied. A twin Bonanza soon made the same request. ‘One-twenty on the ground,’ was the reply. To our surprise, a navy F-18 came over the radio with a ground speed check. I knew exactly what he was doing. Of course, he had a ground speed indicator in his cockpit, but he wanted to let all the bug-smashers in the valley know what real speed was ‘Dusty 52, we show you at 620 on the ground,’ ATC responded. The situation was too ripe. I heard the click of Walter’s mike button in the rear seat. In his most innocent voice, Walter startled the controller by asking for a ground speed check from 81,000 feet, clearly above controlled airspace. In a cool, professional voice, the controller replied, ‘ Aspen 20, I show you at 1,982 knots on the ground.’ We did not hear another transmission on that frequency all the way to the coast.”

This article from Gizmodo about flying the SR-71 is required reading.

In a world of throw-away appliances and software it’s a salient reminder that great work, great engineering lasts a long time. The Skunkworks team was isolated and protected from the rest of the organisation; this one team designed over 30 planes including the U2, A-12, SR-71, F-117, F-22 – just to name a few iconic aircraft.