Re: Landing Gear Loads

Date:         25 Aug 98 00:53:32 
From:         kls@ohare.Chicago.COM (Karl Swartz)
Organization: Chicago Software Works, Menlo Park, California
References:   1
Followups:    1 2 3
Next article
View raw article
  or MIME structure

>plane -- despite every pilot's best effort to grease the landing --
>will be descending at somewhere between zero and, say, 500 feet per
>second when it touches down ... spinning the tires up to ~150knots

500 feet per second is nearly 300 knots.  Yes, I think it's safe to say
that the vertical velocity is between zero and twice the airspeed of the
aircraft at touchdown!

Perhaps an extra zero snuck in there?

>Also, is the reason there is a taxi limit because the tires actually
>experience higher loading/heating during takeoff than landing?

In a normal takeoff, probably not, but keep in mind that the tires need
to retain some semblance of composure in the worst case, which is a
rejected takeoff right at V1.  In many cases that won't be a lot less
than the usual landing speed, except there will be a lot less runway on
which to brake and a lot more energy (due to the higher weight) to get
rid of.  A lot of that abuse goes to the brakes, but the heat which they
generate quickly finds its way to the nearby tires.

--
Karl Swartz	|Home	kls@chicago.com
		|Work	kls@netapp.com
		|WWW	http://www.chicago.com/~kls/
"The average dog is a nicer person than the average person." - Andrew A. Rooney