It seems to me there should be little surprise or controversy over the number of jet or turboprop engines required on an aircraft for safe flight in instrument meteorological conditions or visual meteorological conditions.

The trend appears to be following an economic and efficiency-based pattern that has been progressing since the appearance of jet and turboprop transport aircraft. The industry started originally with four engines and four crew members required as the norm. Next we designed and approved three engines and three crew members.

Now we're operating with two engines and two crew members on many routes. The next step in this cost-saving progression is one engine, one crew member. Obviously, further economic benefits will be attained using one engine and zero crew.

Of course the ultimate in this progression will be no engines and no crew - "Beam me up, Scotty!" Initial public acceptance may be a problem with these more technically advanced schemes.

Capt Robert Kay Seattle, Washington

Source: Flight International