Hard landing: How hard is hard?

[GravityHater]

I've seen it go till 100 hour to get caught.

I've seen it be undiscovered until the next (or later) prebuy inspection too!

My worst landing was my private checkride BOING!! saved a short field 'crash' by going around. Should've failed me for cracking under pressure if not the bad arrival.

 

[EOpilot]

I hear that 727's are hard to consistently make good landings in. Can anyone with som experience in them share some stories or theories?

True. The 727 is challenging to land smoothly. Many say it's because of the location of the landing gear in relation to the CG, especially in the -200 series. That's a bunch of garbage, though. Many aircraft have wheels as far from the CG as the 727.

Really the challenge comes due to the fact that the tail is HIGHLY loaded in the landing configuration. This loading is felt as additional apparent weight since the tail is loaded with downforce. In a flare, the downforce is increased, increasing the apparent weight. Timed just wrong, the flare actually drives the aircraft into the runway even harder than if not flared at all. Timed just right, (and without touching the throttles until 10'), one can "roll it on" by derotating just slightly prior to wheels down, thereby decreasing the downforce of the tail, reducing the apparent weight, and temporarily slowing the rate of descent.

That's all for EOpilot's groundschool for today. Tune in next week when I'll be going over digital cable troubleshooting from my Comcast van.

Ugh.