Improvements in materials, compressor blades, and especially the introduction of multi-spool engines with several different rotational speeds, led to the much higher pressure ratios common today.

As the air travels through the compressor stages it can reach temperatures that pose a material failure risk for the compressor blades.

In engine applications, titanium is used for rotors, compressor blades, hydraulic system components, and nacelles.

By far the largest portion of this pressure difference is on the compressor blades.

This is especially the case with the engine's low pressure turbine blades and the high pressure compressor blades.

During development, there were severe problems with compressor blades, turbine blades and bearings failing at even low power output levels.

The missing seal caused frozen chunks of lavatory fluid to be ingested by the number three engine thus damaging the compressor blades.

Also, the diameter of the compressor blades becomes progressively smaller in higher pressure stages of the compressor.

The compressor blades will then usually come out of stall, and re-pressurize the engine.

Vibration problems with the compressor blades delayed the program at this point, until a new stator design by Max Bentele solved the problem.