K5DH wrote:
Here's an interesting thought. We have some very intelligent, talented, and experienced people here on WIX, including engineers, pilots, and maintainers. Just for fun, let's dream up the ultimate heavy airtanker for today's market. Assume we have a big budget. Would we base our craft on an existing airframe or would we go "clean sheet"? Would we use piston engines or turbines? It might be hard to get Avgas in remote areas, but turbine engines often don't react quickly to throttle changes. We would want to be able to operate from short and/or primitive airstrips. The ship would have to handle well in turbulent air and be maneuverable in tight spaces. Do we want advanced synthetic vision avionics to be able to see the terrain through the smoke? How big a load do we want to carry? Would this be a land plane or an amphibian? Quick turnaround time is important, as is ease of maintenance.
Keep it serious, as if we were going to pitch our design to the US Government for consideration.
What do you suggest, and why?
I'll play. My entry would be a 4 engine turboprop in the 4,000 gallon range. The reasons:
- Straight wing for drop operations, shortish fields. Acceptable cross country transit speed. STOL not worth the tradeoffs.
- Conventional fuselage landplane, not an amphibian. Amphibian not worth the tradeoffs.
- Engines. 4 modern turboprops with modern (~6 blade) props. Good redundancy, acceptable fuel burn, good throttle/pitch response, good transit speed, good loiter, good parts and repair chain, good fuel availability. Pistons are getting to rare and expensive. 2 engines not enough redundancy.
- 4,000 gallon capacity. 3,000 gallon capacity seems to be the sweet spot, or at least what we have been accustomed to, so a slight increase but not getting into the supertaker category which comes with a massive increase in purchase and operating costs.
- Clean sheet would be best from a design perspective, but in reality would never make it certification and profit wise. Maybe a lean scaled composites type approach? Imagine our federal regulators and contract issuers would want a certified aircraft- but that comes at huge expense.
- I think this would end up looking like a modern P-3/Electra- perhaps the stillborn P-7.