ENCL 4 NAVAIR ASW Approval Letter CPT-35.pdf

DEPARTMENT OF THE NAVY

NAVAL AIR SYSTEMS COMMAND

RADM WILLIAM A. MOFFETT BUILDING

47123 BUSE ROAD BLDG 2272

PATUXENT RIVER MARYLAND 20670-1547

11000

Ser AIR-V1.7/074

01 December 2020

From: Commander, Naval Air Systems Command

To: Commanding Officer, Marine Corps Air Station, Cherry Point

Subj: AIRFIELD SAFETY WAIVER CPT-35; MILCON P-199/197 F-35 AIRCRAFT

PARKING

Ref: (a) IBONS submission 12/01/2020

(b) UFC 3-260-01 (Airfield and Heliport Planning & Design)

(c) UFC 2-000-05N (Facility Planning for Navy & Marine Corps Shore Installations)

(d) OPNAVINST 3140.24G (Adverse and Severe Weather Warnings & Conditions of

Readiness)

Encl: (1) MCAS Cherry Point Airshow Layout

(2) MILCON P199/197 Airfield Operations Proposed F-35 Parking Plan

(3) MCAS Miramar F-35 Parking Diagram

(4) Lockheed Martin Facility Requirement Document F-35 Exhaust Plume Diagram

(5) MCAS Miramar SATAF Letter dtd 22 Oct 2020 (VMFA-314 Testimony)

(6) NAVFAC F-35 Exhaust Temperature/Velocity chart

(7) MILCON P199/197 NAVFAC Proposed F-35 Parking Plan

1. Reference (a) requested an airfield safety waiver (ASW) for the F-35 aircraft parking as identified in MILCON P-199 and P-197 that is currently in design. The F-35 aircraft parking configuration as per reference (b) and (c) will not be able to be met, since the number of aircraft per squadron will likely increase from the originally planned number of 10 to 12-16 per squadron. This number is identified in the Commandant of the Marine Corps (CMC) Force

Design 2030. Additionally, MCAS Cherry Point conducts the largest Marine Corps Airshow on the East Coast, and due to the limited amount of real estate and given airfield configuration, the

Airshow is restricted to the aircraft parking options available per enclosure (1).

2. a. UFC 2-000-05N Table 11320-2 requires 200 feet of separation between the aircraft for a

90-degree parking configuration. This table does not differentiate how aircraft will be parked i.e., nose to nose or tail to tail. The aircraft can be parked safely nose to nose, which is less than 200 feet, provided there is enough maneuvering room for the aircraft to exit the sunshade, and turn safely down the interior taxi lane between sunshades shown in enclosure (2). VMFA-314 stationed at MCAS Miramar, park their F-35 aircraft at 145 feet apart nose-to-nose (125 feet between sunshades) as per enclosure (3) with no maneuvering issues. As per enclosure (4), the exhaust from the F-35 at idle poses no concern laterally to personnel and equipment in adjacent sunshades while taxiing. Essentially the F-35 exhaust has a very narrow exhaust plume and does not spread out laterally. Enclosure (5) is a letter from the MCÄS Miramar SATAF stating there are no F-35 exhaust temperature issues as per VMFA-314 testimony.

b. Reference (c) states in Para 11320-4.1 that parked aircraft must be separated to maintain proper wing tip clearance, interior taxi lane widths and protection from jet blast. Jet blast protection is achieved by providing the space necessary to dissipate the temperature and velocity of the jet blast to levels that will not injure or damage aircraft personnel and equipment.

Typically, this level is approximately 100 degrees F and 35 miles per hour (mph) or 30.4 knots.

This level can be easily achieved by parking carrier-based aircraft 45 degrees with their engine blast aimed into the interior taxi lane, providing safe and adequate jet blast dispersion. This requirement is only addressing parked aircraft in a static environment. This is very important because aircraft spend a majority of their time on the ground with engines turning in their parking spots and adhering to these temperature and exhaust velocity requirements is crucial to protecting personnel and equipment.

c. Reference (b) Appendix B, Para B 7-5.1 (Parked Aircraft) states a minimum clearance is needed to the rear of an engine to dissipate jet blast to less than 35 mph and jet exhaust temperatures to 100 degree F or ambient, whichever is more otherwise a jet blast deflector is needed. This requirement is specifically for static parked aircraft and it should be noted that the

F-35 exhaust temperatures would exceed these requirements at 200+ feet separation, which is the spacing requirement cited in reference (c). (See enclosure (6).

d. Reference (b) Appendix B, Para B 7-5.2 (Taxiing Aircraft) states the distance from the rear of the aircraft engine to the wingtip of other aircraft will be a distance such that jet blast temperatures will not exceed 100 degrees F and not to exceed 35 mph. This requirement is unrealistic for fixed wing tactical aviation (TACAIR) aircraft.

e. As currently designed, the NAVFAC parking design for P-199/197 utilizes 220 foot spacing between all F-35 aircraft (200 feet between sunshades) with a 235 foot offset from the hangar; both of which exceed reference (c) parking standards. This is because a peripheral taxiway is typically required by reference (c) between the hangar and nearest row of parked aircraft on the apron. This is typically 150 feet for the taxiway and 50 feet for the access apron totaling 200 feet. The proposed distance per enclosure (1) is 115 to the sunshade and 150 feet to the aircraft. The primary purpose of this requirement is to use for taxiing aircraft. The station has indicated that they will not use this area to taxi active aircraft that is mitigated by the 90-degree parking. This reduced distance, however, does introduce a heat hazard when the aircraft is outbound from the inner parking row as shown in enclosure (6) for 150 feet at 10% and 15% thrust levels. .

f. Reference (d) requires personnel to take immediate safety precautions and shelter whenever a Thunderstorm Warning is in effect. The MCAS Cherry Point Regional METOC Center sets this and other conditions for East Coast Marine Corps Installations to include MCAS Cherry

Point. Due to the convective weather experienced typically between the months of May through

October at MCAS Cherry Point, F-35 aircraft should be parked as close as possible to the hangar without posing a hazard to personnel and equipment working in the hangar. This will allow personnel on the flight line to shelter as quickly as possible. The F-35 aircraft requires extensive maintenance person-hours in order to support flight operations. Subsequently, maintenance personnel are required to haul heavy and bulky toolboxes and test equipment out to the flight line multiple times per day. A typical VMFA squadron does not have maintenance carts to shuttle this equipment to/from the flight line and consequently must be hand carried. Per the NAVFAC proposed F-35 parking diagram, the F-35 aircraft are parked 235 feet from the hangar, which

MCAS Cherry Point Airfield Operations believes is excessive, and will delay personnel from not only seeking quick shelter during Thunderstorm Warning conditions, it will also place undue burden on aircraft maintenance personnel.

g. A portion of the apron being utilized for P 199/197 F-35 parking is currently utilized for transient and detachment aircraft parking which is comprised of fixed/ rotary/ tilt-wing aircraft.

In the future, the new transient line will be located to the east of the F-35 ramp as per NAVFAC proposed parking apron. The P-228 FY20 MILCON project will demolish/ relocate the current

Base Operations, Radar Air Traffic Control Facility (RATCF), Hangar 131 facilities and recapitalize these areas into usable ramp space. Based on the current NAVFAC parking configuration, the exhaust from the F-35' s on the eastern most line (Position 2 of Enclosure 7) will take up valuable ramp space and directly impact available parking space for transient and detachment aircraft.

3. A deliberate risk assessment was conducted by the Installation and validated by NAVAIR and determined to be minor. Many alternatives have been explored, and were determined to be cost prohibitive or impractical. The following risk factors have been evaluated by NAVAIR and the following mitigation measures must be put in place.

a. The F-35 exhaust and velocity concerns when aircraft are exiting and turning out of the sunshades will be addressed by the F-35 Maintenance Marines who are required to wear Personal

Protective Equipment (PPE) on the flight line during flight operations which includes coveralls

(sleeves down) , cranial, goggles, gloves and steel toed boots. PPE offers protection from jet exhaust temperatures, which may be experienced, and is the exact same PPE that is worn during shipboard flight operations.

b. During launch evolutions, the Plane Captain is responsible for everything that occurs around the aircraft pre/post engine start. Troubleshooters (Maintenance Marines) that require working on the aircraft while it is turning in the sunshade. When the pilot is ready to taxi, the

Plane Captain ensures the area is clear in front of and behind the aircraft before clearing the pilot to taxi. All troubleshooters during this time are off to the side of the aircraft and in a position where they will not be swept by the jet exhaust as the pilot turns 90 degrees left or right out of the sunshade. Position 2 of enclosure (2) is an example where the F-35 would turn left out of the sunshade to taxi and sweep the sunshades behind and to the right of the aircraft. All maintenance personnel will be positioned on the north side of the sunshade in order to not get swept by the taxiing aircraft.

c. Due to Foreign Object Debris (FOD) concerns, aircraft parked closest to the hangar taxi first assuming they are parked on the same row. This prevents aircraft from blowing FOD down the intakes of a turning aircraft, and is common practice for Marine Corps fixed wing TACAIR squadrons.

d. Reference (b) states that a peripheral taxi lane is normally provided on all sides of an aircraft-parking apron. It goes on to state that 150-foot wide peripheral taxi lane is to be provided on all sides of a fixed wing aircraft-parking apron. Although such an arrangement is desirable, it is not always necessary. When small numbers of aircraft, (one or two rows) are to be parked or when operational requirements allow, the number and/or width of the peripheral taxi lanes may be reduced on the advice of local Airfield Operations personnel, subject to

NAVAIRSYSCOM approval. Based on these facts, the local Airfield Operations preferred parking plan as per enclosure (2) has the aircraft offset 150 feet from the hangar (115 feet sunshade to hangar separation). All sunshades for P-199/197 are 70 x 70 feet. F-35 sunshades and the aircraft is parked in the middle of the sunshade which is an additional 35 feet from the hangar. This distance poses no hazards to personnel and/or equipment, since a 90 degree parking plan, and peripheral taxiway is not required between the sunshades and hangar. Aircraft are towed in/out of the hangar to/from the flight line, which is the only activity that occurs in this location. During flight operations, this area remains clear.

e. The F-35 idle (10% ETR) exhaust temperature and velocity readings at 150 feet are 37 degrees F exhaust excess temperature and 17 knots (20 mph) per enclosure (6). With an average high of 89 degrees F in July at MCAS Cherry Point, this equates to 126 degrees F at the hangar doors. The exhaust velocity is not a factor at 17 knots and these temperatures would be momentary when the F-35 turns 90 degrees exiting the sunshade. Temperatures and exhaust velocities will only decrease as the aircraft taxis away from the hangar; therefore, these parameters would pose no hazards to personnel and equipment.

f. The MILCON P-199/197 ramp is sloped away from the hangars for drainage purposes, which will help minimize throttle settings while aircraft are taxiing out of the line.

4. Accordingly, an Airfield Safety Waiver is issued as follows:

Waiver Description

CPT-35 To permit F-35 aircraft to be parked at 170 feet nose-to-nose (150 feet between sunshades), as per enclosure (2). Additionally, allow the peripheral taxi lane to be reduced to 115 feet from the hangar, which results in an aircraft engine distance to the hangar door face of approximately 150 feet as it taxis outbound. Operators and flight line personnel should recognize the risk and mitigate where flight line personnel total ambient and excess thrust temperatures exceed 100 degrees F or 35 mph thrust.

5. This NAVAIR ASW does not eliminate the need for a NAVFAC UFC Exemption/Waiver as required by the Mil-Std 3007G for planning, design, or construction. Please contact the

NAVFAC Atlantic Director Engineering Criteria and Programs for need verification and

NAVFAC Chief Engineer approval.

6. Naval Air Systems Command point of contact is Mr. LeRoy Mattingly, AIR V1.7, DSN 757-

2145, commercial (301) 757-2145 and facsimile (301) 757-2167.

12/1/2020

X William F. Cords

Signed by: CORDS.WILLIAM.FREDERICK.1099674403

W. F. CORDS

By direction

MCAS Cherry Point Airshow Layout

Enclosure (1)

VMGR-252

taxi line

200 ft

1 1 2 3

150 ft

115 ft

200 ft150 ft

115 ft

6 x Lines / 7 Sunshades per Line (42 Total) 170 ft nose-to-nose/ 220 ft tail-to-tail / 150 ft from hangar

N

Fuel Truck Apron Access

New Transient Line

Base Ops/ATC

Hangar 131

Enclosure (2)

MCAS Miramar

125 ft

150 ft

Enclosure (3)

F-35 MBIT/HSLT

Position

Lockheed Martin FRD F-35 Engine Exhaust Plume Data

Enclosure (4)

Enclosure (5)

Enclosure (6)

VMGR-252

taxi line

200 ft200 ft

1 1 2 3

4200 ft200 ft 200 ft

200 ft 200 ft

6 x Lines / 7 Sunshades per Line (42 Total) 220 ft spacing between aircraft

N

Fuel Truck Apron Access

New Transient Line

Hangar 131

Base Ops/ATC

Enclosure (7)

1 2