WASHINGTON — NASA released a draft request for proposals (RFP) for reduced-gravity aircraft flights Feb. 20 that a representative of the sole U.S. commercial provider of such services said does little to encourage bids. But a top executive with that provider, Ft. Lauderdale, Fla.-based Zero Gravity Corp. (Zero-G), said the company still hopes to sell parabolic flights to NASA.

“We realize it’s a draft, so we are in the middle of reviewing it and expect to submit some comments [to NASA],” said Byron Lichtenberg, a former NASA space shuttle astronaut who is Zero-G’s co-founder and chief technical officer. “We would like to see it be as streamlined [as possible] and more oriented toward buying a commercial-off-the-shelf product, which is what we have to offer.”

Since September 2004 Zero-G has been treating paying passengers to flights on specially equipped Boeing 727 cargo planes that use parabolic flight maneuvers to produce brief periods of weightlessness. The company also has persistently been trying to persuade NASA to use Zero-G for training and research rather than operate its own aircraft.

NASA bought two trial flights from Zero-G in 2005 and last year agreed to hold a competition to decide whether to buy more flights, keep operating its own parabolic aircraft, or turn the operation of its aircraft over to a private contractor. NASA also moved responsibility for conducting the competition to its Glenn Research Center in Cleveland following complaints by Zero-G that Johnson Space Center in Houston could not be trusted to run a fair competition since it stands to lose jobs if parabolic flight services are outsourced.

While Glenn Research Center is managing the acquisition, source selection authority resides at NASA headquarters here. Steven Miley, director of NASA’s Office of Shared Capabilities, is the source selection official.

David Finney, chief of NASA Johnson Space Center’s Aircraft Operation Division, told Space News in December that NASA would continue to operate its modified DC-9 “unless a lower-cost alternative is identified — with requisite assurances of flight safety, responsiveness and effectiveness — that can meet NASA’s [microgravity] research requirements.”

In its draft RFP NASA officials said they anticipate buying flights for 15 to 20 weeks per year but are not obligated to pay for more than a single week of flights under the envisioned five-year contract. NASA also wants bidders to go back to the companies that made their aircraft to obtain an engineering evaluation of the equipment’s suitability for parabolic flights and follow any recommendations the manufacturer make.

NASA spokesman David Steitz said the reason the agency issues RFPs in draft form is to give bidders a chance to comment on the solicitation before it is issued.

“Part of the procurement process is to get comments from our potential commercial partners,” Steitz said Feb. 26. “We want comments on what the private sector sees as unreasonable or challenges that are prohibitive.”

Steitz said NASA has no intent to structure the solicitation to discourage bids.

“Right now we have an organic capability for these services but we want to procure commercial services provided it is in the taxpayer’s interest to do so,” he said. Lichtenberg said the company has obtained detailed engineering evaluations from Boeing and aircraft engine-maker Pratt & Whitney as part of achieving its Federal Aviation Administration certification.

Of more immediate concern to Zero-G is some of the technical requirements NASA has set for the aircraft. Lichtenberg said the dedicated 747 that Zero-G bought last year in anticipation of bidding on the NASA flights could readily be modified to meet NASA’s electrical requirements for powering onboard experiments.

Zero-G also could install the overboard venting equipment NASA needs, getting rid of combustion products produced in the pursuit of science. But with the contract award expected in August and the first flights expected to commence in September, Lichtenberg said Zero-G would have to make a fair amount of NASA-specific modifications up front with no guarantee of enough NASA business to pay for them.

“That’s not insurmountable,” Lichtenberg said. “But putting all that in to meet NASA’s requirement will require an upfront investment, but this draft RFP right now only requires the government to buy one flight week of four flights and then they’ve met their requirement and can turn [the contract] off.”

Lichtenberg said he does not expect that to happen. But if NASA intends to buy 15 flight-weeks a year, he said, setting that as the contract minimum would provide assurance to bidders such as Zero-G that the aircraft modifications are worth making.

Zero-G board member Robert Walker, a former chairman of the House Science Committee, said he had not seen the draft RFP but had been briefed on it by a Zero-G executive and did not like what he heard.

“It sounds to me as though NASA has done everything possible in the RFP to discourage anyone from even bidding,” Walker said in a Feb. 23 telephone interview. “As I understand it you have to make what would amount to significant investments and then the contract only guarantees you one week of flights in five years. That obviously is a completely foolish situation.”

“The moment NASA ends up having to face the reality of a real commercial contract, they find ways to put every roadblock in place that they can possibly find,” Walker said.