Q A_Round_6_(3-28-13).pdf

DARPA-BAA-13-19

VTOL X-Plane

Questions and Answers – Round 6 28 March 2013

VTOL X-Plane BAA-13-19 Questions & Answers – Round 6

IN THE EVENT OF ANY INCONSISTENCY BETWEEN THE ANSWERS PROVIDED

HEREIN AND THE BAA, THE BAA SHALL TAKE PRECEDENCE

Q49. The time frame to submit an exceptional VTOL X-plane proposal by May 1, 2013 is probably short for most proposers. But still, does a proposer who happened to be selected for Phase I have the choice to revise his proposal by offering a much better concept during Phase I, without facing any kind of penalty?

o A49. The proposal deadline has been extended to June 4, 2013. Selections will be made based on an evaluation of the contents of proposals received prior to this deadline. Because selection is contingent upon the specific concept contained in an offeror's proposal, radical departures from the proposed approach will not be entertained during Phase I.

Q50. Because the systems being proposed are conceptual theory based ideas, it will be necessary for DARPA to evaluate those proposals without the aid of robust mathematic simulation. It will be challenging to detect error in a conceptual system. What metric will DARPA use to evaluate conceptual ideas? Who will evaluate the proposals? How will the concepts be sorted for evaluation?

o A50a. Evaluation criteria can be found on page 35 of the VTOL X-Plane BAA-13-19, which is posted on FedBizOpps at the following link:

https://www.fbo.gov/spg/ODA/DARPA/CMO/DARPA-BAA-13-19/listing.html.

Evaluation of proposals will be accomplished through a scientific/technical review of each proposal. Proposals will not be evaluated against each other since they are not submitted in accordance with a common work statement. Rather, they will be evaluated on the basis of their individual merits.

Award(s) will be made to proposers whose offerings are determined to be the most advantageous to the Government, all factors considered, including technical contributions and the availability of funding for the efforts.

It is the policy of DARPA to ensure impartial, equitable, comprehensive proposal evaluations and to select the source (or sources) whose offer meets the Government's technical, policy, and programmatic goals. Pursuant to FAR 35.016, the primary basis for selecting proposals for acceptance shall be technical, importance to agency programs, and fund availability.

o A50b. In order to provide the desired evaluation, qualified Government personnel will conduct reviews and (if necessary) convene panels of experts in the appropriate areas.

Subject to the restrictions set forth in FAR 37.203(d), input on technical aspects of the proposals may be solicited by DARPA from non-Government consultants/experts who are strictly bound by the appropriate non-disclosure requirements.

Q51. Before truly creditable information can be reported or proposed, a high degree of computation should be part of the development process. What type of scientific, engineering and aerodynamic explanations will DARPA require to effectively evaluate proposals being made for accuracy?

o A51. The proposal needs to be based on concepts and ideas that are founded on achievable, physics-based technology approaches. These should be substantiated to provide confidence that a feasible path forward exists, with the intent of resolving designs and performance details during the execution of the program. DARPA expects to receive scientific, engineering and aerodynamic explanations that substantiate and provide credibility to the proposed concepts based on analytical, computational and experimental data. Additional justification exemplifying likelihood of success based on analogy to prior/existing state of the art, and additional developments thereof, may be submitted to further argue the viability of a concept. DARPA has recourse to subject matter experts capable of advising on technical matters and verifying claims, and will resort to them.

DARPA, however, does not intend to run parallel efforts to independently verify every aspect of performance submitted. It is up to the proposers to provide sufficient detail to justify the likelihood of success of the program proposed.

Q52. Can proposals be made just on sub-processes to support the aircraft development process? For example, new metal panel forming methods or new and innovative methods to create aircraft tooling? These by themselves would be unresponsive to the bottom line goals of the solicitation. However, they might strongly support the overall goals of DARPA and the project. Will DARPA include and evaluate these types of "supporting technology" role submissions in this solicitation?

o A52. The BAA solicits complete proposals that address the objectives of the program in their entirety. Organizations with esoteric technologies and expertise may team-up with other companies in support of the VTOL X-Plane program as suitable. A list of attendees is provided at the Proposers' Day registration website at:

https://www.schafertmd.com/darpa/tto/VTOLXP/index.php?p=attendees.

Q53. Reference: “Sustained high speed flight at true airspeeds between 300 kt and 400 kt.”

(BAA pgs. 5 & 9)

Question: Are these speeds expressed as TAS and at which altitude shall these speeds be achieved?

o A53. Yes, speeds are true airspeeds and may be demonstrated at the best altitude to do so.

Q54. Reference: “Standardized flight profile description. (BAA pg. 10)

Question: Can it be assumed that range for Cruise Out 1 and Cruise In 2 is identical and fall-out/figure of merit? Can it be assumed that the same applies for Cruise Out 2 and Cruise In 1?

o A54. Yes, this may be assumed. The take off and landing points are the same. The ranges for Cruise Out 1 and Cruise In 2 should be provided for the proposed concept.

Q55. Reference: “Standardized flight profile description. (BAA pg. 10)

Question: Is a minimum service ceiling required?

o A55. There is no stipulation on the minimum service ceiling.

Q56. Reference: “The demonstrator aircraft should be designed with sufficient load margins and be able to execute maneuvers from -0.5g to 2.0g at various flight conditions.

(BAA pg. 9)

Question: Is the assumption correct that these load factors has to be performed also out of Hover mode (e.g. pure vertical or lateral movements) in all directions (nx,ny,nz)? Can it be assumed that maneuvers required apply to maximum gross weight?"

o A56. The aircraft should be designed with sufficient load margins to be able to safely demonstrate maneuvers at least up to these load limits at maximum gross weight under different flight conditions. The accelerations are representative of being able to demonstrate maneuverability during take off, hover, transition to and from forward flight, and to perform coordinated turns, etc. Proposers should exemplify maneuver (or V-n) diagrams for their aircraft to establish specific performance envelopes.

Q57. Reference: “System (aircraft) hover efficiency within 25% of the ideal power loading (at sea-level standard conditions), which for open rotors (for example) is given by

PL = (2 / DL)1/2, where PL = T/Pact, T = thrust required to hover, Pact = actual power required to hover, = aircraft non-dimensional coefficient of efficiency, = density of air, DL = T/A, A = equivalent actuator disk area.” (BAA pg. 9)

Question: Shall the hover efficiency be achieved in ground effect (HIGE) or out of Ground effect (HOGE)?

o A57. HOGE at sea level standard.

Q58. Reference: "Payload: The configuration and volumetric assignments for the operational (objective) aircraft must be designed for human occupancy (the payload cannot be divided into more than two separate, roughly equal volumes)" (BAA pg. 29).

This implies that payload shall include human passengers/troops for the operational "up scaled" version.

Question: Would this apply also to payload requirements on the X-Plane demonstrator i.e.

passenger/troop transport space? If yes, up to how many troops shall be assumed? Is the assumption correct that the L/D ratio of 10 already accounts for this wrt. respective impacts?

Question: What are the reference volumetric properties to be used for the X-Plane demonstrator wrt. payload (i.e. reference density)? If passengers/troops shall be considered as payload for X-Plane, what would be the assumption for reference space required by human including ingress/egress of passenger into compartment/troop bay?"

o A58a. The intent of this consideration is to encourage aircraft designs capable of carrying meaningful payload volumes, and to discourage the design of configurations that assume impractical, fractionated payload capacities (that might be distributed over the entire aircraft). The L/D accounts for these impacts. The desired payload for the X-Plane demonstrator is listed as 12.5% GW.

o A58b. For an unmanned aircraft, the volume need not necessarily be configured or rated for human occupancy, but should be capable of holding meaningful, unfractionated payloads. For designs intended to carry troops or personnel, the cabin size should be sized to permit standard troop seating capabilities, which the proposers’ may present as part of the favorable attributes of their designs. The X-Plane, even if flown by an onboard pilot, is not expected to fly with human payload. Other attributes of an aircraft designed differently may also be offered for consideration.

Q59. Reference: "Aircraft Size/Dimensions: Compatibility with air transportation and shipboard operations" (BAA pg. 29)

Question: Does this address air transportation operations and shipboard operations procedures/regulations constraints, or does this implies a requirement for transportability of the aircraft by airlift?

o A59. These considerations ask that any benefits of the proposed design that make it particularly suitable for operations to/from ships, or simplify air/sea transportation, be presented. Some configurations, for instance, may be particularly well suited for ship operations and enable simplified procedures. Any other beneficial attributes, including those not listed in the BAA, may also be described.

Q60. What are the applicable standards for the design of the air vehicle for the demonstrator and the operational aircraft e.g. handling qualities as MIL-F-8785B, MIL-F- 83300, MIL-HDBK-1797 and/or respective airworthiness standards, environmental conditions etc.?

o A60. The VTOL X-Plane must be designed and built to meet experimental airworthiness standards and be capable of safe, fully controlled flight and demonstrate adequate maneuverability in hover, transition and translational flight. Military standards would be applicable to an operational aircraft in response to user specifications, but are not stipulated for the demonstrator.

Q61. Reference: “Capabilities at hot and high conditions (6k ft. 95 deg F).” (BAA pg. 29)

Question: Can it be assumed that these capabilities/conditions address only field/hover performance (Take-Off/Landing, Hover IGE/OGE) and not total ceiling in cruise-flight performance?

o A61. Yes, that is correct.

Q62. Is the vehicle expected to land on a runway as a fixed wing aircraft?

o A62. Not necessarily. But it is expected to be capable of VTOL.

Q63. What is long range cruise?

o A63. Cruise is the ability of the aircraft to cover distances over ground. For long ranges, the assumed expectation would be to fly at best cruise speeds and altitudes.

Q64. In the hover phase, are there any turns or maneuvering objectives?

o A64. The aircraft is expected to be fully controllable. It should be able to yaw, pitch and roll as well as transition to and from forward, sideways and backward flight in both hover and translational flight. The aircraft should be stable/controllable in all flight conditions.

Specific angular or translational rates and accelerations are not stipulated by DARPA.

Proposers should exemplify the capabilities of their aircraft.

Q65. We missed the Proposer's Day and would entertain the option to collaborate our efforts with other interested parties, if there is a resource to investigate networking opportunities, we would be very interested!

o A65. The list of attendees, affiliations, and contact information has been posted to the VTOL X-Plane registration website at https://www.schafertmd.com/darpa/tto/VTOLXP/index.php?p=attendees

Q66. Will DARPA be providing answers to questions submitted in writing at the Proposer’s Day that were not addressed in the open meeting, or must these questions be resubmitted through the web site?

o A66. Yes, and are being posted to https://www.fbo.gov/spg/ODA/DARPA/CMO/DARPA-BAA-13-19/listing.html as Q&A rounds.

Q67. Does DARPA plan to publish answers to the questions submitted at the Proposer’s Day that were addressed verbally in the meeting?

o A67. Questions posed verbally are not being explicitly addressed. Responses to questions received in writing, both during Proposers’ Day and via the BAA mailbox, are being published.

Q68. Regarding speed requirements, the response to a question in the third round states the peak L/D, which must be 10 or greater, is at Vbr. Does Vbr need to be equal or greater than 300 kts?

o A68. No, it is not stipulated that Vbr be 300 kt or greater; however, the speed objective is for sustained and unrestricted cruise capability at speeds above 300 kt at the highest air vehicle efficiency possible. High L/D at high speeds is highly desirable.

Q69. Does flight at an engine’s 30 minute sustained power limit (IRP) satisfy the sustained maximum speed requirement? What about operation at the 10 minute rating (MRP)?

o A69. DARPA’s stipulation is that the aircraft should be capable of sustained flight at high speeds as a consequence of elegant and efficient design, rather than through the application of brute power. Furthermore, the aircraft should be able to fly at these speeds in an unrestricted manner. The VTOL X-Plane should demonstrate the ability to fly at these high speeds at engine power ratings commensurate with the engine selected for the demonstrator. DARPA is interested in verifying demonstrable improvements in efficiency for various flight conditions, but is not imposing time of flight or endurance objectives on the demonstrator.