Lunar Lander Challenged

One small step for NASA, One giant leap for the X Prize

2007 draft rules for public comment

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X Prize Foundation Director of Space Projects Will Pomerantz writes today:

Happy New Year! I hope that the first few weeks of 2007 have been going well for you all, and that you are all starting to look forward to the 2007 Wirefly X PRIZE Cup and the Northrop Grumman Lunar Lander Challenge (NG-LLC).

I’m pleased to announce that the rules for the 2007 edition of the NG-LLC are almost complete. Before we lock them down, though, we want to give you a chance to comment on them. This the best time for you to request clarifications, point out errors, identify loopholes, or request changes in the rules for the 2007 contest. You will note that the rules are quite similar to those used in 2006; however, there have been a few minor tweaks and clarifications.

Please feel free to comment on any section of the rules; however, I would like to draw your attention specifically to the following items:
– Gold Box: Similarly, I have heard requests that XPF provide (free or at cost) a standard Gold Box, rather than allowing teams to construct their own. If you have a strong opinion on this, please voice it.
– Refueling: You will note that the new section A.2.19.1 constitutes one of very few substantive changes to the rules from the 2006 edition. If you disagree with the change, please let us know.
– Payload: I have heard requests that XPF provide a standard payload, rather than allowing the teams to provide their own. If you have a strong opinion on this, please let us know.
– Propellants: Our list of allowable propellants is not yet finalized, pending the finalizations of our agreements with our host venue. This is the most accurate list available at present.
– Vehicle Reference Point: This replaces the “Vehicle Centerline”, which was deemed unnecessarily complex. If you disagree with the change, please let us know.

All changes after this public comment period will be at the sole discretion of the X PRIZE Foundation and NASA—however, we greatly look forward to your input. Please feel free to pass this message along to other parties you know may be interested—though I ask that you please not post my phone number (in my signature, below) on any websites.

Once we have reviewed your comments and accommodated your requests wherever possible, we will finalize the changes, publicize the final rules, and open registration. This timeline will ultimately depend on NASA’s concurrence cycle—but we hope that this will occur in mid-February.

The public comment period begins now, and will end at 5:00pm EST on Monday, January 22nd, 2007. Comments should be submitted to will@xprize.org with the subject “NG-LLC Comments”.

Kind regards, and thank you in advance for your comments,
William

William Pomerantz
Director of Space Projects
X PRIZE Foundation

NORTHROP GRUMMAN LUNAR LANDER CHALLENGE RULES
NON-BINDING DRAFT COPY – FOR PUBLIC COMMENT ONLY
A.1 Overview

The Northrop Grumman Lunar Lander Challenge is designed to accelerate technology developments supporting the commercial creation of a vehicle capable of ferrying cargo or humans back and forth between lunar orbit and the lunar surface. Such a vehicle would have direct application to space exploration goals as well as the personal spaceflight industry. Additionally, the prize will help industry build new vehicles and develop the operational capacity to operate quick turnaround vertical take-off, vertical landing vehicles, which will be of significant use to many facets of the commercial launch procurement market.

The complete Northrop Grumman Lunar Lander Challenge purse of $2,000,000 is divided into two levels: Level One, worth a total of $500,000, and Level Two, worth a total of $1,500,000. To win prize money in either level, a rocket-propelled vehicle with an assigned payload must take-off vertically, climb to a defined altitude, fly for a pre-determined amount of time, then land vertically on a target that is a fixed distance from the take-off point. After remaining at this location for a period of time, the vehicle must take-off, fly for a pre-determined amount of time, and land again on its original launch pad. The primary difference between the two levels will be in the time of flight, the surface terrain at the landing sites, and the corresponding degree of difficulty presented for precision landing and servicing of the vehicles.

A.2 Definitions Specific to Challenge

A.2.1 Challenge – The Northrop Grumman Lunar Lander Challenge. Additional Titling or Presenting Sponsor names may be added by XPF at any time.

A.2.2 Challenge Termination – The Challenge will be offered until such time as all the Purses have been won, or until the conclusion of the 2010 X PRIZE CUP. This 2010 deadline may be extended at the sole discretion of NASA. Prize Purses may be supplemented in the future pending availability of funds at the sole discretion of XPF.

A.2.3 Competition Level – The Challenge is divided into two levels: Competition Level One, worth a total of $500,000; and Competition Level Two, worth a total of $1,500,000. The primary difference between the two Levels will be in the time of flight, the surface terrain at the landing sites, and the corresponding degree of difficulty presented for precision landing and servicing of the vehicles.

A.2.4 Competition Venue – The location and duration of the “Wirefly X PRIZE Cup” event, as determined by XPF.

A.2.5 Demonstration Flights – One test flight of the Vehicle performed before arriving at the Competition Venue. The flight must be of the minimum flight time of 90 seconds for Level One and 180 seconds for Level Two. The flight must be observed by XPF. The Vehicle may be tethered during the Demonstration Flight. Any test flight required by the Federal Aviation Administration may be counted as the Demonstration Flight if desired by Team, provided it meets the minimum flight time requirement described above.

A.2.6 Flight Attempt – The operation of the Vehicle at the Competition Venue intended to satisfy all the rules for winning the Challenge.

A.2.7 Finalist – Any Qualified Vehicle that successfully meets or complies with all Technical Flight Requirements (section A.4) and other rules of the Challenge for the indicated Competition Level.

A.2.8 Gold Box – A group of systems, which together are referred to as the “Gold Box”. The Gold Box shall contain cameras and sensors used to monitor, record for later playback, and simultaneously broadcast Flight video and data to an XPF mission control. All Gold Box systems must be supplied by Team and must be demonstrated at the Competition Venue at least 48 hours prior to the Flight Attempts. The mass of the Gold Box may be counted as part of the required mass of the Payload so long as the systems are not also essential to the operation of the Vehicle, as determined by the Official Judges.

A.2.8.1 Video Component: Gold Box must obtain and transmit acceptable video images from a minimum of two cameras. If possible, team is requested to provide output from three cameras. One camera must be a downward facing “landing camera”, and one camera must image the Logo Cluster and the horizon.

A.2.8.2 Position and Telemetry System: Gold Box must transmit two methods of identifying altitude, one of which must be a GPS signal. Gold Box must provide accurate readings used by the Official Judges to ensure compliance with the Challenge rules, including Vehicle position and heading while in flight.

A.2.8.3 Transmission and Storage System: Gold Box must provide the appropriate transmitters, antennae, and on-board storage required both to store these signals for later use and to downlink these signals in real time to an XPF-provided ground station. Team shall coordinate with XPF both on data formats and the frequency or frequencies used to downlink.

A.2.9 Landing Accuracy – The distance from the Vehicle Reference Point to a designated target on the landing Point.

A.2.10 Logo Cluster – A pre-defined arrangement of logos, supplied by XPF, to be placed on the exterior of Vehicle

A.2.11 Mean Landing Accuracy – The arithmetic mean average of Landing Accuracies from all qualifying landings.

A.2.12 Official Judges – Independent Challenge evaluators appointed by XPF to assure compliance by Team to the rules and regulations governing the Challenge, validate all measurements required for determining Finalist and Tie-breaker status, and to determine the relative positions of the Vehicles for the Level One and Level Two Challenges.

A.2.13 Payload – A 25kg mass that is not propellant or part of the airframe, structure, or other systems that are involved in the flight, operation, or maintenance of the vehicle. The Payload must be labeled and measurable. The weight of the Gold Box systems may be counted as part of the mass of the Payload, so long as these systems are not essential to the operation of the Vehicle, as determined by the Official Judges.

A.2.14 Point A – The assigned initial launching and final landing site for a Team’s Vehicle. Teams will be provided with position coordinates for Point A within 60 days of the Flight Attempts. Teams will be responsible for verifying Point A site positions that are consistent with their own guidance and navigation system approach and capabilities.

A.2.15 Point B – The assigned landing and second launching site for a Team’s Vehicle. The geometric center of Point B will be horizontally displaced by approximately 100 meters but by no more than 120 meters from the geometric center of Point A. This is the target where the vehicle will land and be serviced before taking off vertically for its return flight to Point A. Exact point locations will be assigned by XPF. For Level One, Point B will be on a relatively flat, hard, and hazard-free simulated lunar surface without boulders. For Level Two, Point B will be on a simulated lunar surface, with local slopes and hazards such as boulders. Position coordinates for Point B will be provided to Teams within 60 days of the event. General information regarding the nature of the Point B surface for Competition Level Two will be provided to teams by XPF no later than 60 days before the Flight Attempt. Teams will be responsible for verifying Point B site positions that are consistent with their own guidance and navigaton system approach and capabilities.

A.2.16 Private Sources – Non-government (U.S. or other) sources. Money won in previous years of the Northrop Grumman Lunar Lander Challenge is deemed acceptable.

A.2.17 Purses – A total of US$2,000,000 (two million U.S. dollars) is available to be won.

A.2.16.1 Level One First Prize is $350,000 (three hundred fifty thousand U.S. dollars).

A.2.16.2 Level One Second Prize is $150,000 (one hundred fifty thousand U.S. dollars).

A.2.16.3 Level Two First Prize is $1,000,000 (one million U.S. dollars).

A.2.16.4 Level Two Second Prize is $500,000 (five hundred thousand U.S. dollars).

A.2.16.5 Purses not claimed in any given year will carry over to future years until won or until the Challenge Termination.

A.2.18 Qualified Vehicle – Any Vehicle that has satisfied the Challenge Conditions as detailed in Sections A.3.7 through A.3.9.

A.2.19 Refueling Operations – Loading of propellant, replacement of motor cases, propellant grains, nozzles, or combustion chambers, or changes to control software. No repair or maintenance of flight safety critical items due to flight-induced damage or maintenance will be allowed. Flight safety critical items will be determined by the Official Judges of the Challenge in consultation with the Team Leader. Refueling operations must be pre-approved and will be monitored by the Official Judges of the Challenge for conformance. Failure to conform will disqualify the Flight Attempt.

A.2.19.1 Teams may replace instruments or systems damaged by flight if and only if spare parts are carried aboard the Vehicle during flight from Point A to Point B, and if the replaced parts are carried aboard the Vehicle during flight from Point B to Point A. Such spare or replacement parts cannot be counted as part of the Payload.

A.2.20 Staging Area – An area provided and designated by XPF wherein Team will store and prepare Vehicle in preparation for or following a Flight Attempt. The Vehicle must be in the Staging Area at the beginning of any Time Period. Hazardous materials intended for use or storage in the Staging Area must be pre-approved by XPF.

A.2.21 Time Period – A pre-assigned 150-minute period wherein a Qualified Vehicle may attempt to meet the Technical Flight Requirements.

A.2.21.1 Each Qualified Vehicle will have an assigned Time Period of one hundred and fifty (150) minutes to safely transport the Vehicle from the Staging Area designated by XPF to point A, successfully meet the Technical Flight Requirements (section A.4) as measured by the Official Judges of the Challenge, and safely transport the Vehicle back to the designated Staging Area.

A.2.21.2 These Time Periods will be assigned to Qualified Vehicles at a pre-determined time by a random drawing conducted by the Official Judges of the Challenge.

A.2.21.3 Qualified Vehicles will be granted as many Time Periods as possible, as determined by XPF, given the total number of competing Qualified Vehicles and the total available time for that year’s Challenge. All Qualified Vehicles will be granted the same number of Time Periods.

A.2.21.4 If a Qualified Vehicle is unable to fly in an assigned Time Period, the Official Judges of the competition may reassign that slot to another Qualified Vehicle. Reassignments will be made at the sole discretion of the Official Judges of the Challenge.

A.2.210.5 The Official Judges may elect at their sole discretion to extend a Time Period due to external forces such as weather, pending availability of time.

A.2.21.6 The Official Judges may elect at their sole discretion to assign a Team to a future Time Period, pending availability of Time Periods.

A.2.21.6 When required, XPF will reserve a number of Time Periods for use by Finalists. Finalists shall be assigned to these Time Periods by the procedures described in section A.5.

A.2.22 Vehicle – The Team’s entry in the Challenge, not including the Payload or ground support equipment, consisting of a single, all-inclusive unit carrying all propulsion, avionics, and other flight subsystems as appropriate. The Vehicle must have a flight safety system, a pre-approved system designed to limit or restrict the hazards to the uninvolved public by preventing the Vehicle from reaching a populated area in the event of a failure.

A.2.22 Vehicle Number – A number assigned to each Vehicle by the Official Judges 30 days before the Competition. This number will stay with the Vehicle throughout the competition of that year, and will be used to identify the Vehicle, including for any random draws required. Any changes of Number without the knowledge and written approval of the Judges will disqualify the vehicle from competition.

A.2.23 Vehicle Reference Point – A clearly marked and accessible point on the exterior of the Vehicle defined by Team prior to any Flight, which shall be used for measurement of Landing Accuracy.

A.2.24 Vehicle Storage Areas – An area provided and designated by XPF wherein Team will store and carryout pre- and post-competition maintenance check out of Vehicle prior to moving to Staging Area. Any special storage requirements must be specified by the Team and agreed to by XPF 60-days prior to the Challenge.

A.2.25 XPF – The X PRIZE Foundation, responsible for administering, executing, and judging the Challenge.

A.3 Challenge Conditions

A.3.1 Technical specifications not already covered in this Agreement about any Challenge detail will be provided by XPF to the Team at the time of registration. These technical specifications may be subject to reasonable future updates by XPF at its sole discretion no later than 90 days prior to the Challenge for those changes that might affect design and no later than 30 days for those changes affecting operations.

A.3.2 The Challenge will be conducted until Challenge Termination.

A.3.3 Team shall provide or make arrangements for all necessary test facilities, personnel, equipment, fluids, and consumables necessary to complete the flight and to transport the Vehicle between the Vehicle Storage Area, the Staging Area, Point A and Point B. The team shall be solely responsible for environmental protection of their vehicle in all Areas and its associated equipment and consumables during storage, maintenance, transport, and operation.

A.3.4 All Flight Attempts to win the Purse(s) must take place from the Competition Venue during assigned Time Periods.

A.3.5 Purses will be distributed according as follows:

A.3.5.1 If only a single Team becomes a Finalist in a given year, then that Team will win the largest Purse not previously awarded in that Competition Level.

A.3.5.2 If more than a single Team becomes a Finalist in a given year, then those Teams will be ranked according to the tie-breaker criteria described in section A.5. Teams will then be awarded the highest Purses not previously awarded for that Competition Level according to their ranking.

A.3.5.3 No Vehicle can win more than one Purse in a single year of the Challenge.

A.3.5.4 A Vehicle may be registered for Competition Level One or Competition Level Two, but not both.

A.3.6 Team must provide certification to XPF at least 60 days prior to the Challenge that at least 90% of the funds used to design, build, and operate the Vehicle come from Private Sources.

A.3.7 Team must provide documentation to XPF at least 30 days prior to the Challenge proving the Vehicle has received appropriate licenses, waivers, or permits from the applicable regulatory bodies, including, if necessary, the Challenge Venue site..

A.3.8 Team must invite XPF to attend, observe, and document the Demonstration Flight at least three weeks prior to the Flight Attempt. XPF must receive advanced notice at least one week prior to the Demonstration Flight.

A.3.9 Team must notify XPF at least 120 days prior to the Challenge which propellants, oxidizers, and other consumables will be used at the Competition Venue by the Vehicle for all flights. Decisions regarding the safe use of all consumables shall be made at the sole discretion of XPF.

A.3.9.1 The following fuels and oxidizers shall be considered safe for operation at the Competition Venue: butane, ethane, ethyl alcohol, gaseous oxygen, gasoline, hydrogen, H20, H202 in concentrations less than or equal to 90%, isopropyl alcohol, kerosene, liquid oxygen, methane, N20, propane.

A.3.9.2 The following fuels and oxidizers shall be considered unsafe for operation at the Competition Venue: H202 in concentrations greater than 90%, nitric acid, hydrazine, unsymmetrical dimethylhydrazine, monomethylhydrazine, any hypergolic propellant combination.

A.3.9.3 All other fuels and oxidizers shall be reviewed by the Official Judges of the Challenge to ascertain compliance and the potential for safe usage at the Competition Venue. Teams may request this judgment at any point after the naming of the Official Judges.

A.3.10 Prior to any Flight Attempt:

A.3.10.1 Teams desiring to compete must register with XPF (See Appendix A: Registration Form) by an XPF appointed date for the year in which the Team plans to compete. For the 2007 Competition, this date shall be 17:00 PDT on TBD. If desired by the Team, Team Registration data will be kept confidential until 60 days before the Flight Attempt date, at which point it will be made public and promoted by XPF.

A.3.10.2 A Team Data Package (See Appendix B: Team Data Package) must be provided to XPF by an XPF appointed date for the year in which the Team plans to compete. For the 2007 Competition, this date shall be 17:00 PDT (Santa Monica, California local time) on TBD. This deadline may be extended at the sole discretion of XPF.

A.3.10.3 Teams must sign and return this Agreement toXPF by an XPF appointed date for the year in which the Team plans to compete. For the 2007 Competition, this date shall be 17:00 PDT (Santa Monica, California local time) on TBD. This deadline may be extended at the sole discretion of XPF. This Agreement addresses multiple issues including but not limited to sponsorship rights, media rights, and liability. Teams and all Team members must abide by this Agreement.

A.3.10.4 Teams must provide a detailed Mission Schedule, including step-by-step operations and approximately timelines, to the Official Judges of the Competition, no later than 17:00 PDT (Santa Monica, California local time) on TBD. This deadline may be extended at the sole discretion of XPF.

A.3.11 The Vehicle shall meet all of the required Gold Box and safety functions on all flights at the Competition Venue.

A.3.12 The Vehicle shall clearly display an external identification of the Vehicle Reference Point and the Vehicle Number.

A.3.13 The Vehicle shall clearly display a Logo Cluster provided by XPF.

A.3.14 The Vehicle shall carry the Payload during all Flight Attempts.

A.3.15 Only Qualified Vehicles shall be allowed to perform Flight Attempts at the Competition Venue.

A.3.15.1 In any given year of the Challenge, the number of Qualified Vehicles permitted to perform Flight Attempts at the Competition Venue may be limited at the sole discretion of XPF. For 2007, the number of Qualified Vehicles shall be limited to TBD for Level One and TBD for Level Two.

A.3.15.2 Vehicles that meet the definition of Qualified Vehicle shall be permitted to perform Flight Attempts at the Competition Venue, until such point as the limit of Qualified Vehicles described in Section A.3.15.1 has been reached. Vehicles that meet the definition of Qualified Vehicle after the limit for a given year has been reached shall not be permitted to perform Flight Attempts at the Competition Venue for the given year.

A..3.15.3 Vehicles will be declared Qualified in the order in which Qualification verification, as defined in Section A.3.13.2, is completed. In the case of a tie for the last opening for a given year, preference will be given to any Team that does not already have one Qualified Vehicle for that year. If two or more Teams all have one Qualified Vehicle or all lack a Qualified Vehicle, the opening will go to the Vehicle that first submitted first submitted a complete Registration Package.

A.3.16 The Vehicle shall meet all the Technical Flight Requirements given below. The Technical Flight Requirements described in section A.4 must be performed in the sequence given, and none may be omitted or rearranged.

A.4 Technical Flight Requirements

A.4.1 After the start of Team’s assigned Time Period, Team must transport Vehicle safely from the XPF-designated Staging Area to Point A and ready Vehicle for take-off.

A.4.2 Vehicle must take-off vertically utilizing only rocket power from Point A. No aerodynamic or air-breathing methods of hovering, propulsion, steering, or landing are permitted except in the case of abort.

A.4.3 Vehicle must vertically ascend from Point A to a flight altitude of no less than 50 meters. The choice of exact flight altitude is the sole decision of the Team, but must comply with all safety regulations. The Vehicle must be initially located with its Vehicle Reference Point above the geometric center of Point A, as marked by XPF or the Official Judges. The Vehicle Reference Point must remain within a cylinder 10 meters in diameter and 50 meters high, centered about the geometric center of Point A for the ascent to be considered vertical. The Vehicle must maintain an altitude of at least 50 meters as it translates horizontally from above Point A to above Point B.

A.4.4 Vehicle must remain aloft for a minimum amount of time. For Level One this minimum is 90 seconds. For Level Two this minimum is 180 seconds. Flight time will be measured by the Official Judges from the time the last Vehicle contact point leaves Point A, until the first Vehicle contact point touches Point B, initiating a stable landing. Re-contact during either takeoff or landing will not be counted in determining vehicle flight time.

A.4.5 Vehicle must land and shut down engines within a 10 meter diameter circle centered on a marked target at Point B. No part or portion of the Vehicle may make contact with the ground outside of the 10 meter diameter circle centered upon Point B. Vehicle must remain at Point B long enough for the Official Judges to measure the Landing Accuracy.

A.4.6 While the Vehicle is at Point B, Team will have the option to perform Refueling Operations on its vehicle. The Vehicle may not be relocated from its landing position at Point B, but Vehicle may be leveled if required for safety and/or guidance requirements. If some non-essential functional component of the vehicle is dislodged as the result of landing at Point B, it may not be reattached, but the vehicle is allowed to proceed with a subsequent takeoff attempt. No maintenance to repair damage caused by the flight or landing is permitted at Point B. No replacement parts may be added to the Vehicle unless the replacement part was carried aboard the Vehicle during all previous Flights, and the replaced part is carried aboard the Vehicle on all subsequent Flights.

A.4.7 Vehicle must take-off vertically utilizing only rocket power from Point B. No aerodynamic or air-breathing methods of hovering, propulsion, steering, or landing is permitted except in the case of abort.

A.4.8 Vehicle must vertically ascend above Point B to a flight altitude no less than 50 meters. The choice of exact flight altitude is the sole decision of the Team. The Vehicle Reference Point must remain within a cylinder 10 meters in diameter and 50 meters high, centered about the position of the Vehicle Reference Point prior to takeoff, for the ascent to be considered vertical. The Vehicle must maintain an altitude of at least 50 meters as it translates horizontally from above Point B to above Point A.

A.4.9 Vehicle must remain aloft for a minimum amount of time. For Level One this minimum is 90 seconds. For Level Two this minimum is 180 seconds.

A.4.10 Vehicle must land and shut down engines within a 10 meter diameter circle centered on a marked target at Point A. No part or portion of the Vehicle may make contact with the ground outside of the 10 meter diameter circle centered upon Point A.

A.4.11 Team must transport Vehicle back to the XPF-designated Staging Area before the conclusion of the assigned Time Period.

A.4.12 Any Qualified Vehicle that has successfully met all of the requirements of this Challenge for Competition Level One or for Competition Level Two shall be considered a Finalist in the appropriate Competition Level.

A.5 Finalist Time Period

A.5.1 Tied Finalists for each Competition Level will select desired 150-minute Finalist Time Period from the options identified by XPF. The Finalist that achieved the smaller mean landing accuracy shall have first selection of Time Period.

A.5.2 In the event of a tie for first, second, or third place in Level One or Level Two, the tied Finalists for each Competition Level shall use the assigned Finalist Time Period to accumulate the maximum number of flights from Point A to Point B and from Point B to Point A, used to rank the tied Finalists.

A.5.2.1 All Vehicles must meet all Technical Flight Requirements (section A.4) during the Finalist Time Periods, with the exception of the minimum hover times described in sections A.4.4 and A.4.9.

A.5.2.2 Total number of flights from Point A to Point B or from Point B to Point A during the assigned Finalist Time Period shall be monitored and tracked by the Official Judges of the Challenge. The total number of flights from Point A to Point B and the total number of flights from Point B to Point A shall be summed, so long as each flight occurs within the assigned 150-minute Finalist Time Period and all other Challenge requirements are met.

A.5.2.2 If the entire Vehicle is not returned to the Staging Area by the end of the 150-minute Finalist Time Period, all Flights from that Finalist Time Period shall be invalidated.

A.5.2.3 The Vehicle with the greater number of total flights, as described in Sections A.5.2.1 and A.5.2.2, shall be considered the higher ranked.

A.5.3 In the event that the tie breaker described in Section A.5.2 has been applied and there is still a tie between any number of Finalists in either Competition Level, Vehicles will be ranked by Mean Landing Accuracy for all Flight Attempts, including those occurring during Finalist Time Periods. The Vehicle with a smaller Mean Landing Accuracy shall be considered the higher ranked.

A.5.4 In the event that both tie breakers have been applied and two or more Vehicles are still tied, the purse money shall be split evenly between these Vehicles.

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Written by Robin

January 16, 2007 at 4:02 am

Posted in lunar lander

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