Has America’s Economy Entered The “Coffin Corner”?

 | Jul 10, 2014 03:10AM ET

Summary: Growth slows in the developed nations due to several factors, as debt levels rise. Have we entered the “coffin corner” where we cannot growth sufficiently fast to service our debt? This is the follow-up to The dilemma of the US economy: can’t take off & too close to the brink .

In the absence of effective and comprehensible economic theory, economists often rely on analogies. Such as comparisons with aerodynamics. Flying complex vehicles at high speed under variable conditions, often with inadequate or old information — the role of pilot has similarities with that of central banker.

A common mistake of bankers is raising rates to curb inflation while the economy is in fact on the brink of recession. That’s similar to a “graveyard spiral“, in the past a frequent cause of crashes. From Wikipedia , slightly edited:

Graveyard spirals occur in nighttime or poor weather conditions with no horizon visible to provide visual correction for misleading inner-ear cues. … The pilot mistakenly believes the wings to be level, but with a descent indicated on the instruments, so the pilot attempts to climb. In a banking turn, however, the plane is at an angle and flying in a large circle. This tightens that circle, causing the plane to fall at an increasing rate.

This flying by “the seat of the pants” and failing to recognize instrument readings is the most common source of “controlled flight into terrain”.

Today the US economy might have flown into conditions similar to another perilous aerodynamic situation — the coffin corner. From the Sky-brary (slightly edited):

The coffin corner (aka Q Corner) is the altitude near which a fast aircraft’s stall speed equals its critical Mach number. As an aircraft climbs towards the altitude that defines its coffin corner, the margin between stall speed and critical Mach number becomes smaller and smaller until the Flight Envelope boundaries intersect. At this point any change in speed creates serious problems. Turning the aircraft could result in exceeding both limits simultaneously, as the inside wing slows down and the outside wing increases speed. Encountering turbulence can push the aircraft outside its flight envelope.