If you're in cruise flight, how could you ever get slow?

GA Aircraft vs. Jets

When you're cruising in a light aircraft, you probably don't spend too much time thinking about getting close to a stall at altitude. That's because it rarely, if ever, happens.

But when you're flying a jet, it's a real possibility. Here's why...

Jet Engines + High Temps = Bad Combo

Jet engines are a lot more sensitive to temperature increases than reciprocating engines. That's because they rely on drawing air into the engine, compressing it as much as possible, igniting it with fuel, and then accelerating the hot air out the back of the engine to produce thrust.

And for jet engines, the more they can heat the air passing through the engine, the more power then can produce.

That becomes a problem when you're flying in warmer-than-normal air. The turbine section of an engine can only get so hot before it melts (which nobody wants). So if you're flying in warm temps, your engine can't use as much fuel to heat the air, which means it can't create as much thrust out the back of the engine.

Why Are You Getting Slow?

Today's modern aircraft are typically thrust limited, which means they run out of thrust before they get anywhere near coffin corner. And the reason this is more common now, is because today's supercritical wings are significantly more efficient than wing designs from decades ago that you would have found on a DC-8 or 727.

Essentially, on aircraft like the CRJ, the wing can fly higher than the engines can.

Flying Into Warm Air

Getting slow and close to stall at altitude can happen when you climb into a temperature inversion or fly into a warm air mass. If the temperature changes quickly, so does the power output of your engines. And if you're near your thrust limited ceiling, you can start slowing down quickly.

How Do You Recover?

So what happens if you start getting slow at altitude? The first thing to do is add max continuous thrust. Most of the time during cruise in a jet, you're using an economy power setting. By adding more power, you can (in many cases) accelerate back to the airspeed or Mach number you want. But, if your engines can't produce enough thrust to maintain speed, you'll need to descend, trading altitude for airspeed.

Keeping Your Speed

Rapid temperature increases can cause real problems for jets at altitude. But by keeping a close eye on your speed, and knowing what to do if you get slow, you can keep yourself from getting near a stall buffet.

So where do you learn about all of this? In your ATP CTP course, which happens right before your type training at an airline. And at ExpressJet, the training is provided in-house, and for free (wahoo!). Plus, you'll learn about more than just high altitude engine performance. You'll go through upset recovery training, control-performance instrument flying, and a whole lot more that you might not already know.

Ready for the right seat in a jet? Apply to ExpressJet today.