Technological development of fighters occurred so rapidly that by December 1941 both the P-39 and P-40 were approaching obsolescence, even though both had been in production less than 18 months.

Very good models are inexpensive, and unlike many technologies approaching obsolescence, current C.R.T.'s are probably as good as they can be.

Today these terms are approaching obsolescence, although many stores still use them.

The crematorium was opened in 1932 but by the 1960s was becoming inadequate for the growing number of cremations, and its equipment was approaching obsolescence.

After 2000, cassette-based Walkman products (and their clones) were approaching technological obsolescence as the cassette format was gradually phased out.

And now, with electronic media panting hard on its heels, the book itself may be approaching obsolescence.

The cartridge is now approaching obsolescence, as shooters turn to other similar but more powerful and flexible loads.

In the mid-1960s, with the advent of improved radar and early-warning capabilities, the radar picket escort ship was rapidly approaching obsolescence.

Worse, by the time the last weapons in a stretched-out production run reach the field, they may be approaching obsolescence.

In some instances, their machines were badly dated and rapidly approaching obsolescence.