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HELICOPTER AIR SERVICE PROGRAM 133

Senator MONRONEY. By what percentage is the payload less as you use it on VTOL against the 250-foot STOL? 

Mr. THAYER. Cruise, compared with hover, is a little over 30 percent of the fuel and torque required. I would like to ask Dr. Hesse to compare that with the STOL operation. 

Dr. HESSE. Actually for a relatively short range, say something under 500 or 600 miles, you can off-load some of your fuel and still carry the full payload in terms of passengers that we indicate up here, and take off vertically. 

Senator MONRONEY. Take off vertically with the full payload?

Dr. HESSE. Yes, sir. 

Senator MONRONEY. The fuel consumption would be greater, would it not? Would that be significant in terms of costing the price of the commuter ticket? 

Dr. HESSE. There would still be adequate fuel for, say, a stage length of 500 or 600 miles, half the load of the normal fuel capacity. If you talk of extreme range, say a thousand miles, you can begin to tradeoff runway distance STOL with payload. 

Senator MONRONEY. In other words, if you wanted to, you could certainly take off from the Washington National Airport, or perhaps even a runway along the park here between the Capitol and the Washington Monument, and get off very easily on one of the highways? 

Dr. HESSE. Yes, sir. 

Senator MONRONEY. And land downtown on the lakeshore front rather easily in Chicago? 

Dr. HESSE. No problem whatsoever. 

Senator MONRONEY. That would be STOL. Or you would even say--that is a thousand miles STOL, about 500 VTOL?

Dr. HESSE. Right. There is a table in the paper. I will give two numbers out of that as an example of this question. With a 10,000-pound, or 5-ton payload, we can take off vertically with a gross weight of 39,650 pounds, and fly a range of 700 statute miles. 

If we want to overload the same payload and take off short takeoff distance, with a gross weight of 43,350 pounds, our takeoff distance there is 320 feet to clear a 50-foot obstacle. Here our range is 1,150 statute miles. 

Other numbers are in this table. 

Senator MONRONEY. You have a tremendous range. 

If suburban commuters would allow you to substitute passenger weight, that is why I mentioned standees. For a short haul of 30 minutes or so, if it could be made comfortable, with seats and standees as well, you could have a carrying capacity by off-loading fuel and could accommodate them, particularly picking up the last portion of the haul? 

Dr. HESSE. Yes, sir. 

Senator MONRONEY. We asked for figures from the ATA about the potential of vertical aircraft, short-haul city center to city center short-haul transportation. The question was asked of ATA--do you think this is one of the areas of greatest promise? For example, assume a vertical aircraft with a speed of 185 miles per hour downtown-to-downtown service, against the fixed-wing plus groundtime, Washington to Philadelphia, which would take 110 minutes, under VTOL 43