AC 91-45C
k. Rotorcraft Takeoff and Landing Areas.
During some aviation events there may be helicopters taking "VIP's" for rides or serving as emergency vehicles. The landing and takeoff areas used by these aircraft should be enclosed in a manner that prevents unauthorauthorized persons from entering the helipad. The helipads should be located so the aircraft does not pass over spectators during takeoff or landing. Regardless of the emergency or nature of the operation, spectators must not be endangered.
Sailplane Operations. Airshow aerobatic demonstrations with sailplanes are becoming more numerous around the country. Sailplanes, by their very nature, are less hazardous than powered aircraft. Sailplanes do not have engines and propellers, nor do they carry flammable liquids that could cause injury to spectators. For these reasons, the following criteria apply ONLY TO SAILPLANE OPERATIONS.
(1) Sailplanes fall into the Category III group. Category III showline and performance distances apply.
(2) Because of the sailplane's need for a tow by either an airplane or a car, taxiways are often used for takeoff. This is advantageous in many cases since it allows the tow plane, towline, and the sailplane to be positioned without congesting the active runway or affecting the operation of powered aircraft. Unless there are obstructions that would make a taxiway takeoff unsafe, it should be permitted with a minimum distance from the primary spectator area of 200 feet (Appendix 1, Figure 14). This distance may be reduced to 150 feet when the takeoff path, beginning at or near the center of the spectator area, is at an angle of at least 10° away from spectators (Appendix 1, Figure 15).
(3) Landings may be approved on the taxiway used for the takeoff as long as there are no obstructions or adverse wind conditions that would create a hazard to the spectators. If the landing approach requires a low altitude turn over 12 2/1/90 spectators, landing on the taxiway shall not be permitted.
(4) This part does not apply to motorgliders which are treated as powered aircraft.
16. POLICING. There is no specific requirement for the use of uniformed police or security guards. The need for special policing depends upon several factors.
a. If fencing is used for crowd control, there may be little need for special crowd-control personnel. On the other hand, if the sponsor intends merely to cordon off the primary or secondary spectator areas with rope, it might be necessary to have special crowd-control personnel.
b. With respect to crowd control, remember that it is the sponsor's--NOT the FAA's responsibility--to ensure that all reasonable efforts are made to confine spectators to the primary and secondary spectator areas. If reasonable efforts have been taken and unauthorized persons or vehicles enter the area where aviation event aerobatic maneuvers are performed, efforts must be made to remove them from the area. Good judgment should be used when determining whether it is necessary to halt a show to protect persons on the ground.
One policing need that is often ignored is the airspace where aviation event aerobatic maneuvers are performed overlaps roads or highways. This can present a problem unless arrangements are made to control traffic. If a road runs beneath the operating area and that road is not patrolled, motorists could park on the shoulders to enjoy the show. If this condition exists, arrangements should be made to have the traffic controlled. Transition over a road or highway underlying the operating area is the same as egress or ingress over congested areas. There is no requirement for termination of an aviation event aerobatic maneuver at a given distance from a road or highway, but, as with a congested area, aviation event aerobatic maneuvers may not Chap 2 Par 15
2/1/90 be performed over roads or highways unless the road or highway has been closed and no persons are allowed to park along the road or highway.
d. If there are farmhouses or other buildings below the airspace where aviation event aerobatic maneuvers are performed, a reasonable effort to evacuate such buildings during the aviation event should be made. If persons reenter the buildings, every effort should be made to evacuate them again.
17. EMERGENCY FACILITIES. Generally, the FAA shall not require much more in terms of emergency facilities than are normally found at airports. Off-airport sites can be another matter, and, before selecting such a site, serious consideration should be given to emergency facilities at such sites. Every aviation event sponsor is encouraged to provide emergency medical service even though this service is not normally necessary. Many sponsors prefer to have the local fire department's emergency rescue squad, paramedics, or emergency medical technicians at their show rather than a physician. Normally, the following rules of thumb are adequate:
Physician. Except for events that are a great distance (in a ground vehicle) from a hospital or medical clinic, an emergency rescue squad, paramedics, emergency medical technicians, or a first-aid station can be substituted for a physician.
Ambulance. If an emergency rescue squad is provided, an ambulance should also be provided. If there is a physician in attendance, any vehicle acceptable to the physician for emergency transportation is sufficient. Many communities rely on a sheriff's or local law enforcement officer's vehicle as their only means of ambulance service. It would be improper to prohibit use of a similar vehicle to serve as an ambulance for the event.
c. Firetruck. For the most part, the only reason for having a firetruck at an aviation event is for performers' benefit, not the spectators'. If Chap 2 Par 16 AC 91-45C the performers are willing to accept a pickup truck with handheld fire extinguishers, the FAA does not demand a sponsor provide an official firetruck with trained firemen.
d. Crash Wagon. Many locations where events are conducted do not have crash wagons available. If they are not available, the FAA does not require a sponsor to obtain one from a facility that might be hundreds of miles away.
Again, the presence of crash wagons benefits the pertormers, not the public.
e. Aerobatic school activities or aerobatic meets, which are not aviation events, contests, or races, require a waiver. At these school activities or meets not advertised as aviation events, it may not be necessary for the school or sponsor to provide policing or emergency facilities.
Some professionai performers do not accept a contract or an invitation unless liability insurance has been obtained and/or adequate first aid and emergency medical transportation are provided. Also, performers might demand that, for their own protection, a firetruck with trained personnel be provided.
18. FAA FORM 7711-2. FAA For 7711-2, Application for Certificate of Waiver or Authorization (Appendix 1, Figure 16), is used when applying for FAA Form 7711-1, Certificate of Waiver or Authorization (Appendix 1, Figure 17).
The local FAA FSDO assists in the preparation of FAA Form 7711-2; however, the preparation and submission of FAA Form 7711-2, as well as all of the necessary supporting documentation, are the responsibility of the applicant.
b. Depending on the type of aviation event or operation, all items on the form may not be applicable. In other cases, additional information may be required.
AC 91-45C
c. An application for an aviation event must be submitted at least 45 days before the date of the scheduled event.
d. An application for a parachute jump must be submitted at least 4 days before the scheduled event.
Upon receipt, the FAA FSDO reviews the application for accuracy. Because the inforsubmitted on FAA Form CANNOT be altered by the FAA FSDO, the FAA inspector-in-charge will arrange a meeting in order to correct the application.
f. Upon approval by the FAA FSDO, FAA Form 7711-2 becomes a part of FAA Form 7711-1 (Appendix 1, Figure 17).
19. SCHEDULE OF EVENTS. The FAA must see a schedule of events in order to evaluate the application. The schedule of events does not 14 2/1/90 need to be detailed. However, it should contain at least a general description of the types of events (e.g., aircraft aerobatic performances, skydivers, car/plane transfer, etc.), the identification of the aircraft, and the performers in the sequence of their appearance.
a. A date must be specified when a schedule of events will be provided.
Any demonstrations added to the "Schedule of Events" require FAA approval. Any additions should be submitted to the FAA for consideration at the earliest opportunity. Cancellation of events does not require advance notice to the FAA. However, press shows or other flight activity occuring outside the approved dates and times are not considered additions. A revised or new waiver application will be required.
20.-24. RESERVED.
Chap 2 Par 18
SECTION 2. MANAGING THE AVIATION EVENT
25. PRESHOW ACTIVITY.
Schedules and priorities have a tendency to get hectic before the start of even a properly planned event, e.g., performers asking when and where the briefing is to take place, fire department personnel trying to find out where their trucks and ambulances are to be stationed, concession stand operators looking for electrical outlets, etc. If sufficient, responsible personnel have not been assigned to handle each aspect of the numerous functions associated with a successful event, last-minute problems can appear.
b. Preshow Briefing. One thing that is required of all waivers for aerial demonstrations is the preshow briefing of all performers. For performing teams, it is permissible for just the team leader or other performing member to attend in lieu of every member. The team leader or other performing member must then assume the responsibility for briefing each of the other members of the team. It is imperative that the briefing cover every aspect of the event. The following list of subjects shall be covered at every briefing:
(1) Weather brief.
(i) Who gives the briefing, i.e., sponsor, Flight Service Station specialist, etc.
(ii) Source of information.
(iii) If forecasts are involved, the valid time of forecasts.
(2) Runway in use.
(3) Taxi instructions.
(4) Performer aircraft parking.
(5) Aviation event radio communication frequencies.
(6) Emergency procedures.
(7) Showlines.
(8) Area avoidance.
(9) Review of provisions on the FAA waiver.
(10) Review of the schedule.
(11) Aircraft departure plan.
(12) Next briefing (if necessary).
(13) Questions.
(14) Credential check and signing area.
(15) ALL participants sign waiver.
(16) Fueling procedures.
Departure from Other Airports. At an airport location where a performing or fly-by aircraft will depart from a location other than the airshow site, a telephone briefing must be conducted with the pilots of those aircraft.
Nonairport Location Briefing. If the event is to be conducted at a nonairport location, special procedures for the briefing of the pertormers must be established. The performers must be informed well in advance of the briefing date, time, location, and if appropriate, directions to where the briefing will take place. In addition to the subjects listed in paragraph 25b, the briefing should cover any subjects unique to the aviation event location (e.g., desert terrain, mountainous area, site near water, etc.).
26. AVIATION EVENT PERSONNEL.
Chap 2 Par 25 15
AC 91-45C The actual number of individuals assigned to air and ground operations duties will vary dependent upon the size of the event. It may range from 3 or 4 people at a small aviation event to 50 or more at a large aviation event. It is important that all tasks be addressed and that no individual is so burdened that safety is compromised.
b. The aviation event director or a designated representative is responsible for all aspects of presenting the aviation event. It is his or her duty to set policy and monitor the conduct of the aviation event.
c. An independent safety observer should be assigned by and report directly to the aviation event director. An independent safety observer should use a checklist to monitor all air and ground operations activities throughout the aviation event. During the aviation event, the independent safety observer should immediately report any unsafe situation to the aviation event director.
d. It may be appropriate to have an assistant operations director to divide tasks.
However, it is important that the final authority for air and ground operations authority be with one individual and not several who are working on numerous, independent tasks.
A primary responsibility of the air and ground operations director is to complete early and ongoing communication with the airport manager, FAA FSDO, and Air Traffic Control representatives. These individuals and representatives must be aware of aviation event activities and be kept informed.
f. Air and ground operations coordinators are responsible for accomplishment of all aspects of the specific area to which they are assigned.
The following is a list of coordinators recommended by the International Council of Air Shows (ICAS):
(1) Act coordinator.
16 2/1/90
(2) Display aircraft coordinator.
(3) Maintenance support coordinator.
(4) Housing/Transportation coordinator.
(5) Special event coordinator.
(6) Military teams coordinator.
(7) Fly-in coordinator.
(8) Aircraft security coordinator.
(9) Operations assistants.
Operations assistants are individuals assigned to the various coordinators as necessary.
For example, four assistants might be assigned to help park aircraft, or they may be a person speccifically assigned to operate a radio in the tower.
All tasks of the air and ground operations staff might be accomplished by 1 or 2 people until approximately 30 days before the event. However, as the aviation event date approaches, the coordination and implementation of tasks is beyond the capability of one or two people. The appropriate number of staff coordinators should be identified and assigned early.
This helps to prevent crisis management in the final days before and during the event weekend.
Written records should be required of all coordinators. These might consist of memos, records of phone calls, completed forms, records of meetings, checklists, and critiques. The idea is to have a clear and verifiable means to determine that all tasks have been completed and to create accurate records which may be used in future planning.
An air and ground operations checklist is a good tool to guide the staff through its various essential tasks. It should be adjusted to fit the specific event and built upon from year to year.
Chap 2 Par 26
2/1/90
k. Administration is the management of all avialable resources. The management of all available resources is best conducted through effective communication and recordkeeping, both internally and exterally to other departments.
Each person on the air and ground operations team is responsible in some way for the administrative process.
27. FLYING PARTICIPANTS.
Each participant should have operational information pertinent to the scheduled aviation event before arriving at the site. It is recommended that a copy of the completed FAA Form 7711-2, including diagrams, maps, charts, photos, etc., be forwarded to participants at the same time the application is submitted to the FAA. It is recommended that participants be made aware of aircraft servicing procedures, where and when the aviation event briefing will take place, the time and location of any airworthiness inspections, and any additional information which will help participants be informed before their arrival. The idea is to impart as much operational information as practical in advance so that participants are not deluged at the last min- Chap 2 Par 26 AC 91-45C ute with operational procedures and instructions on top of an already packed schedule of activities.
b. Aircraft rides for hire and media flights are two unique flight operations which frequently must be addressed by aviation event organizers.
Permission to conduct aircraft rides for hire is based upon the same criteria that is applied to any other participant. Thorough planning and thought should also be given to the times rides are allowed, the ingress/egress safety of passengers, and positive security control of the entire aircraft-ride ground operation.
Qualified aviation event participants have a keen interest in the conduct of a safe operation. The primary safety check-and-balance used by the aviation event organizer is the establishment of the credentials of each participant and his or her aircraft, confirmation of the participants' experience in an aviation event environment, and provision to each flying participant with the proper information regarding operations at that specific event.
28.-30. RESERVED.
17 (thru 22)
CHAPTER 3. MILITARY DEMONSTRATION TEAMS
31. SCOPE AND CONTENTS. The guidelines in this chapter apply to military aircraft, military pilots, and parachute teams specifically designated to perform missions for the Department of Defense (DOD).
to exit over a congested area and the determination of authorized passengers during performances. DOD accepts the responsibility for these technical judgments with respect to the safety of the jump exhibition.
32. APPROVED PROFILES. All performances shall be in accordance with a planned profile approved by the applicable command.
various military teams shall provide the FAA with approved maneuver packages. Send to:
FAA General Aviation Staff, AFS-20 800 Independence Ave., SW Washington, D.C. 20591
33. DOD SANCTIONED TEAMS. The aerial demonstration teams sanctioned by the DOD are the U.S. Air Force "Thunderbirds" and the U.S.
Navy "Blue Angels."
34. OTHER MILITARY TEAMS NOT SANC- TIONED BY DOD. Other military teams who frequently perform at public events are the Army and Navy Service Academy Teams. Operations by the academy teams are maintained by their respective academy staff. The requirements for a performance by a DOD nonsanctioned team shall be the same as those for a civilian team.
35. MILITARY PARACHUTE TEAMS. One DOD-sanctioned military parachute team is the U.S. Army Golden Knights. The Golden Knights have two demonstration teams as well as competition teams (e.g., the Black Team and the Gold Team). Therefore, more than one unit operating under the designated team name could be jumping at two different locations. The U.S. Navy "Leap Frogs" are also a DOD-sanctioned parachute team.
The military team determines site acceptability, effect of wind conditions, and location of exiting the aircraft. This includes the decision AR FAA Merm 7/22-2 must de submitted to the FAA FSDO having jurisdiction over the area in which the jump will occur. The application must contain a statement that the military command or service has determined that adequate safety margins exist at the demonstration site for the scheduled demonstration by the specific team on a specific date.
Other military jump teams, such as the U.S. Navy's "Chuting Stars," are not DOD-sanctioned. They may be allowed to perform the same jumps as civilians with a USPA Class C or D license. Determination of site acceptability, wind conditions, and location of exit from the aircraft (including exit over congested areas) shall be made by the team leader. DOD accepts the responsibility for these technical judgments with respect to safety. An FAA Form 7711-2 shall be submitted to the FAA FSDO having jurisdiction over the jump area.
36. TEAM QUALIFICATIONS AND TRAIN- ING. The proficiency and ability of the members of military units are determined by the military command. Therefore, members of military demonstration teams should not be questioned about their competency to perform their approved routines.
37. MILITARY PARTICIPATION. DOD requires that a DOD Form 2535, Request for Military Aviation Participation, be completed for all military aircraft events not conducted on a military installation. To obtain a copy of DOD Form 2535, contact the nearest local military installation. DOD Form 2535 must be completed by the event sponsor or a designated representative. The sponsor or representative must forward Chap 3 Par 31 23
AC 91-45C DOD Form 2535 to the appropriate FAA FSDO for the completion of the feasibility determination.
DOD requires that any event requiring a waiver of the FAR must have the proposed site classified as either "satisfactory" or "unsatisfactory" during a feasibility study of the site conducted by an FAA inspector. A "satisfactory" classification indicates that following compliance with requirements, a waiver can be issued. An unsatisfactory" classification indicates that the site is not approved for the requested military operations portion of the aviation event. If the site is marked "unsatisfactory" by the FAA, the request is not accepted by DOD.
38. SPECIALIZED TEAMS. The armed forces also sanction specialized teams which demonstrate the capabilities of one particular aircraft, e.g., the U.S. Air Force F-16 Tactical Demonstration These specialized teams also develop maneuver packages which define the aerobatic routine to be performed at aviation events.
list of pilots authorized to conduct the aerobatic routines may be obtained from the FAA FSDO.
Only designated aircraft and pilots may perform at aviation events in which FAR § 91.71 is waived. Demonstrations by these speciali.
teams must have command approval. If the local national guard group wants to perform aerobatics at an aviation event, a maneuvers package, approved by its command, must be submitted for review and approval well in advance of the periormance.
39. ARRIVAL DEMONSTRATIONS. Military aerial demonstration teams may wish to put on an arrival show when they fly into the site of a scheduled aviation event. This normally consists of several passes for visual familiarity with existing landmarks and the practice of maneuvers using these landmarks. If a waiver is required for the arrival demonstration, the details should be worked out during the meeting with the FAA FSDO inspector-in-charge. The FAA will approve the arrival show provided it can be safely accomplished.
24 2/1/90
a. If the arrival show means aerobatic operations over populated areas, the show shall not be authorized. A good rule of thumb for determining whether or not an arrival show will be approved is,Will everything necessary for the event itself be taken care of except crowd control and emergency facilitiesi If the answer to this question is NO, then an arrival show can only consist of normal flight operations conducted within the FAR.
team "advance man" accept the arrivat show The military often asks to have the briefing and relay all necessary information to the If the advance man is a rated aviator serving with the team, this should be allowed.
Briefings with the team leader, or a representative, must be completed before the team's arrival at the local show site.
40. FOREIGN MILITARY TEAMS. The considerations and procedures of this chapter also apply to military teams sanctioned by other countries.
41. DOD FEASIBILITY STUDY. Before a DOD-sanctioned aerial demonstration team or parachute team accepts an invitation to participate at an aviation event, DOD requires that the FAA conduct a feasibility study to determine whether or not the proposed operation can be conducted.
Sponsor Responsibilities. It is the responsibility of the event sponsor to obtain and to submit DOD Form 2535 to the FAA.
b. Conducting a Feasibility Study.
feasibility study is normally conducted during the late summer months for an aviation event that will take place the following show season.
Normally, an on-site inspection is required, as a minimum, to determine the status of new construction or other environmental changes in the
c. Inspector Requirements. If the inspector believes that the 7.5 series Topographic Quad- Chap 3 Par 37
2/1/90 rangle Map for the area is necessary to conduct the feasibility study, the inspector will request the map from the sponsor of the event. This may be necessary at a site where the U.S. Navy "Blue Angels" or the U.S. Air Force "Thunderbirds" are appearing for the first time or at sites where new construction may affect a location's suitability for an aviation event.
42. SPECIAL WAIVER PROVISIONS. While the FAA has emphasized the need to maintain standard aviation event separation requirements at sites where it can be accomplished, the aerial demonstration teams may request and receive a special waiver of FAR §§ 91.79(b) and (c) for nonaerobatic flight at altitudes of 200 feet above the highest obstacle within a 3 nautical mile distance from the designated show center along the approved ingress/egress route to and from the aerobatic maneuvering area. The request for the special waiver by the Commanding Officer of the military team should be approved provided:
a. An on-site survey of the demonstration area has been completed by the Commanding Officer of the military demonstration team or a designated member of the team.
A meeting with the Commanding Officer or a designated member of the team, the waiver applicant or designated representative, and the appropriate representative of the FAA FSDO has been held to discuss the potential impact of the operation on the surrounding area.
FAR §§ 91.79(b) and (c), minimum safe altitudes, A letter requesting a special waiver of from the Commanding Officer or the designated member of the team is provided to the FAA FSDO. The letter should specify the altitudes and area over which the special waiver is required. The letter should also state that the Commanding Officer or the designated member of the team, as an authorized representative of the DOD, has completed an on-site survey of the Chap 3 Par 41 AC 91-45C proposed area of operation, has discussed the impact of the operation with the event waiver applicant and the appropriate FAA FSDO representative, and that the demonstration, as provided to the FAA in the command maneuvers package, can be safely conducted in the area. It should further state that the Commanding Officer will accept full responsibility for the operation.
DOD has agreed to approve official demonstration events only when safety is not derogated. Under no circumstances will flight at altitudes less than 500 feet above ground level (AGL) be conducted over designated spectator areas nor shall aviation event aerobatic maneuvers be conducted over spectator or congested areas.
e. While the guidelines in this chapter are primarily oriented to U.S. military precision flight demonstration teams, the procedures may also be applicable to foreign teams. A Letter of Authorization for lower than standard minimums for foreign military teams shall be issued by AFS-20, and only under special circumstances.
Any questions a sponsor may have involving a team should be directed to:
U.S. Army Parachute Team Operations Officer Box 70126 Ft. Bragg, NC 28307-0126
(919) 396-2036 U.S. Navy Blue Angels Events Coordinator NAS Pensacola, FL 32508
(904) 452-2585 U.S. Air Force Thunderbirds Air Show Coordinator P.O. Box 9733 Nellis AFB, NV 89191
(702) 652-9593
43.-48. RESERVED.
25 (thru 30)
CHAPTER 4. AIR RACE COURSE DESIGN
49. SPONSOR RESPONSIBILITIES. The sponsor has the responsibility to lay out the course in such a manner so as to prevent hazards to spectators and other persons on the surface.
50. PERSONNEL. Only persons and vehicles authorized by the race organization at the event should be permitted beyond the crowd line during racing operations.
Authorized persons include press, crews, and officials at the start line.
b. Authorized persons should clear the runway and move back to at least the runway "hold short" line 1 minute before launch for standing starts. No one should be permitted in front of the front row of aircraft after this time except the starter flag team.
Pylon crews (except the home pylon flag crews), press, and vehicles should remain inside the pylon course during races. Race timing teams are permitted in the area between the crowd line and the showline during racing.
51. TYPICAL RACE COURSES. A diagram of a typical air race site is shown in Appendix 1, Figure 18. A map of a typical unlimited race course (Reno, NV) is shown in Appendix 1, Figure 19. Four examples of suitable air race site diagrams are shown in Appendix 1, Figure -
20. The method of determining the various distances used are discussed in the following paragraphs.
52. RACE COURSE DESIGN. Closed-course pylon air racing is conducted over a fixed, shortdistance race course, usually located on or adjacent to an airport. The design of a satisfactory pylon air race course involves the shape of the course itself and the relationship of that course to the spectator areas. Both of these depend upon the maximum speed that may be expected from the racing aircraft and the maxium "g" loading (acceleration forces) that the race aircraft are expected to encounter when flying the race course in a normal manner. Additionally, the maximum height at which race aircraft are expected to fly during the race becomes a factor.
53. RACE COURSE SPEEDS. The following speeds are typical speeds for each racing class.
a. Formula Vee: 160 miles per hour.
b. Sport Biplane: 210 miles per hour.
c. AT-6/SNJ: 225 miles per hour.
d. International Formula One: 250 miles per hour.
e. Unlimited: 450 miles per hour.
f. When additional classes become active, they should be added to this list with appropriate speeds specified.
The maximum "g" loading for a race aircraft flying the course in a normal manner has been set at 3.5 "g's." Note that in actual racing, maneuvering turbulence encountered, momentary "g loadings in excess of this figure can be expected.
The speed and "g" loadings permit the calculation of the minimum radius turn that should be permitted in the design of the race The formula for the tur radius for a given "g" loading and speed is: (Using a value of 3.5 for "g," the minimum turn radius is shown for each racing class in Appendix 1, Figure 21.)
R =
32.2 x R Minimum turn radius Aircraft ›peed (ft/sec) Chap 4 Par 49 31
G = Max acceleration (ft/sec?)
32.2 = Acceleration of gravity (ft/sec?)
i. The angle of the turn (the change in course required to negotiate the turn) should be planned so that it will avoid forcing a race aircraft to make the tum too sharply. A maximum tum angle that does not exceed 65° has been found to be satisfactory.
(1) A maximum racing altitude of 250 feet is acceptable for aircraft weighing in excess of 1,000 pounds (presently, the AT-6/SNJ and the unlimited class), and a maximum racing altitude of 150 feet is acceptable for aircraft weighing 1,000 pounds or less (presently the Intemational Formula 1, Sport Biplane and Formula Vee Classes). The length of the scatter distance for each racing class is shown in Appendix 1,
54. RACE COURSE SHOWLINE. During the race, aircraft occupy a raceway around the race course. The edge of this raceway closest to the 2 x A spectator area is generally the showline over S = V _ X which no aircraft is permitted to pass while 32.2 Scatter distance The raceway width may vary from V = Aircraft speed (ft/sec) 150 feet to 500 feet in the various racing classes A = Aircraft altitude (AGL) to allow aircraft to pass one another. The critical 32.2 Acceleration of gravity (ft/sec?)
requirement is that no racing aircraft is permitted to pass over the showline during the race. (2) The locus of all possible debris impact points from an aircraft in a turn describes a The minimum turn radius, the maxi- circle whose radius is the square root of the sums mum turn angle, and the raceway width define of the squares of the turn radius and the scatter the limits of a satisfactory race course. The race distance. This radius is called the "scatter radius" course relationship to the spectator areas (or other (Appendix 1, Figure 21).
populated area should also be defined. Racing classes with a maximum speed of 250 miles per Sr (R' + S) hour or less require a spacing of 500 feet between the spectators and the showline. The un- Sr = Scatter radius (feet) limited racing class (or other new classes with R = Turn radius (feet) speeds in excess of 250 miles per hour) requires Scatter distance (feet) a spacing of 1,000 feet between the spectator and the showline. (3) In order to provide an acceptable margin of safety, the differences between the tur
c. An additional safety area is required to radius and the scatter radius are multiplied by a ensure that spectators are protected in the event safety factor of 1.5 and added to the turn radius that debris leaves a race aircraft. Should this to define the "safety radius" (Appendix 1, occur while the aircraft is in a turn, the debris Figure 21).
will follow a path tangential to the turn at the moment it departs the aircraft. The straight line Sfr = R + 1.5 x (Sr - R) distance that the debris will fall before hitting the ground (ignoring air resistance) will depend upon Str = Safety radius (feet) aircraft speed and arcraft altitude. This distance Sr = Scatter radius (feet) is called the "scatter distance." R = Turn radius (feet) Chap 5 32 Par 53
2/1/90
(4) The turn that is critical with respect to the safety radius is the turn that enters the portion of the race closest to the spectators.
The safety area is constructed as follows:
(i) Divide the angle for the turn in question in half.
(ii) Mark off the minimum turn radius for the class of aircraft racing as shown in Appendix 1, Figure 21, from the pylon position to a point on the angle bisector.
(111) Draw an arc whose radius is the safety radius from the point located in paragraph 54b. No spectator areas should be within this arc.
(5) In some cases, it may be expedient to design the race course around the spectator Chap 4 Par 54 AC 91-45C While spectator-to-showline distances are unchanged, the safety zone is now outside the spectator area and is no longer a factor. Roads to this kind of a race course layout must be completely closed off to the spectator area during the
(6) Race courses are normally flown in counter-clockwise direction (left Problem sites may require flying the course in a clockwise direction (right tums). Other modifications of the race course, such as changing the angular relationships of the spectator line (to move the crowd away from a tur pylon) or lengthening the race course (to move the turn pylon away from the crowd) may also be necessary.
55.-58. RESERVED.
33 (thru 38)