Designing and Integrating New ER-2 Instruments
ER-2 Payload Areas
Scientific instruments flown aboard the ER-2 can be mounted in the removable nose compartment, the Q-Bay (equipment bay), the wing pods, or the fuselage centerline pod. On a single flight, the ER-2 can carry numerous different instruments to altitudes above 65,000 feet and outside 95% of the Earth's atmosphere.
Equipment Bay (or Q-bay)
The primary payload compartment on the ER-2 is the equipment bay. Also known as the Q-bay, this compartment provides 1.829 cu. m. (64.6 cu. ft.) of volume and features removable upper and lower hatches. The upper and lower Q-bay hatches can be changed and configured to accommodate a wide variety of specialized sensors. The payloads are installed on rack assemblies which are hoisted into the Q-bay through the lower hatch opening and attached at structural mounting points.
Attached to the ER-2 fuselage via four quick release latches, the nose area provides a payload volume of 1.35 m3 (47.8 ft3). The 256 cm (101 inch) long nose compartment accepts payloads of up to 295 kg (650 pounds) on custom built racks. At cruise operating altitude, the nose area environment is maintained at 8.23 km to 9.14 km (27,000 to 30,000 feet) pressure altitude.
The wing superpods provide approximately 2.44 m3 (86 ft3) of payload capacity. Each superpod may accommodate payloads up to a maximum weight of 295 kg (650 lb.). The superpods consist of five individual segments. These are: nose cone, forward pod, mid-body, aft pod, and tail cone. Normal separation points via latches are at the forward and aft ends of the superpod midbody. The forward two-thirds of the superpod, including the nose, forward pod, and mid-body, are pressurized to an equivalent pressure altitude of 30,000 feet or lower. The aft pod area remains unpressurized. 16 in. glass window ports are available for the forebody, while the aft tail cone has an open viewing port.
Fuselage Centerline Tank/Wing Pylon Mounted Tanks
The fuselage centerline tank can be attached to the fuselage underside, aft of the main landing gear. The fuselage centerline tank offers a payload volume of .396 m3 (14 ft3) and 159 kg (350 lb.) each. The centerline tank is unpressurized and lacks temperature control. For certain applications, two pylon-mounted tanks may be mounted on the wings at the superpod attachment locations. Aerodynamic and inertial considerations require that both wings be equipped with the same pod type.
Specialized wing pods have been designed and fabricated for unique applications. Examples of this include collection of cosmic dust and other particles found in the stratosphere.
The Integration Process
Missions involving the ER-2 are planned, implemented, and managed by the Airborne Science Branch. Integration of any instrument payload is performed at Dryden by Lockheed Advanced Development Company (the "Skunk Works") engineers and technicians with oversight by NASA.
Prospective investigators and NASA payloads personnel wishing to design and install a new flight instrument on the NASA ER-2 should follow the integration process presented here.
The twelve step process for integration of any instrument on the ER-2 is outlined in this section. The complexity of the integration effort will determine the time-line involved in this process. The nominal values for schedule dates are based on hundreds of package integrations over more than 20 years of operation.
Three areas wherein the investigator strongly influences the integration time line are:
- Initial notification of the requirements for the instrument.
- Timely interface with NASA and Lockheed Engineering concerning instrument design, constrution, or integration details and requirements.
If these factors are not given sufficient attention at the proper points in the integration process, significant time delays and cost overruns can occur.
All new instruments are integrated at Dryden Flight Research Center at Edwards Airforce Base, California. Data collection missions may be conducted from other bases which meet the needs of scientific objectives. Instruments are integrated by Lockheed Advanced Development Company (the Skunk Works) engineers and technicians, with oversight by NASA Engineers.
In most cases, the interface engineering details will be sent directly to Lockheed Engineering. Scheduling, funding, and coordination priorities and responsibility will be handled by NASA. This entire process is actually a team effort between NASA, Lockheed Engineering, and the investigator. Through cooperation, timely funding, and accurate information exchange, the twelve-step integration process can proceed smoothly and efficiently. The twelve steps in the integration process are as follows:
- Contact the Engineering Manager of the Airborne Science Branch of NASA Dryden as soon as the need to place an instrument aboard the ER-2 is considered. You will be sent an ER-2 Investigator's Handbook, and you will be added to the database of ER-2 principal investigators. Any initial questions you have will be answered at this time.
- After you have reviewed the ER-2 Investigator's Handbook and are confident that the ER-2 will fulfill your needs, contact the NASA Engineering Manager again, to arrange for a teleconference or meeting between yourself, the NASA Engineering Manager and the Lockheed Program Manager to discuss your project.
- Approximately one year prior to an engineering test flight and planned data collection flights, the investigator will need to present the proposed instrument package to the System Review Board at Dryden. The board consists of department heads from NASA and Lockheed Engineering, flight operations, maintenance, and data facility personnel. During this meeting the participants should voice any concerns related to the proposed instrument. In this presentation, the investigator should address in detail the following subjects:
The more clearly and precisely investigators are able to state the requirements, the more precisely NASA-Dryden can determine the resources necessary to meet these objectives. These objectives will be stated on a standard flight request which will be forwarded to NASA headquarters for approval or rejection. Dialogue with the ER-2 operations staff prior to submitting the flight request is welcomed and encouraged. Many flight time restrictions or problems can be worked out at this time. If technical facts are needed to strengthen the request, the operations staff will always be able to either provide answers, or point to a technical source. The operations staff can be reached at NASA-Dryden Airborne Science Branch.
- Research objectives
- Physics of the instrument package
- Desired location of the instrument on the aircraft
- Any other instruments expected to be flown in combination aboard the ER-2
- Operational requirements including: pilot interface, geographical location of operation, season, cloud cover, etc.
- Maintenance requirements, including: installation, access, training, field operations, safety, etc.
- Data acquisition requirements involving decoding, recording, telemetry, formats, calibration, quick field checks, etc.
- Expected electrical power, weights, size, volume
- Ground support requirements such as lab space, power, specialized equipment, gas handling, ground safety requirements for lasers, etc.
- Within four to six weeks following the review board meeting, an informal cost estimate and schedule will be prepared by engineering.
- At this point, the investigator must send adequate funding along with accurate physical and electrical definitions of the package to NASA/LADC Engineering at Dryden. The schedule prepared in step four will be strongly influenced by the timely receipt of funding and definition.
- A Preliminary Design Review (PDR) will be presented by the investigator and/or Lockheed to NASA Engineering. This will normally take place five to six months prior to the initial engineering test flight.
- Any changes to the instrument package will be reviewed by Lockheed Engineering. Significant changes could require another PDR moving the process back to step 5, or a slip in the engineering test flight schedule. Depending upon the complexity of the instrument, a Critical Design Review (CDR) may be required.
- The Final integration Design Review (FDR) will be conducted by NASA/Lockheed Engineering and the investigator. The investigator need not be present at Dryden for the FDR to review and approve the drawings. This review will occur according to the schedule established in step four, and will normally precede manufacture and assembly of interface hardware. For instruments which include active emitters of radiation, the investigator should begin the process of obtaining operating approval from the Radiation Safety Committee.
- The instrument will be expected to arrive at Dryden for airworthiness checks and compliance with drawings, integration fit checks, electrical ground checks and final integration into the aircraft a minimum of three weeks prior to a test flight. The ER-2 maintenance section will furnish up to two man weeks of integration support at no added cost.
- The investigator should plan to participate during the integration period to assist and train operations, maintenance, and data handling personnel. The investigator will verify satisfactory operation of the instrument package. The investigator will also be responsible for providing a ground and flight checklist. This check list should include actions for both the normal, and failed conditions. The investigator will be required to conduct a safety briefing of the instrument for the maintenance crew, and supply material safety data sheets as appropriate to Lockheed Engineering.
- When all ground check and integration activities are completed, and acceptable, the Review Board will conduct a Flight Readiness Review (FRR). This will take place prior to the engineering test flight.
- A nominal 2 hour engineering test flight will be conducted at Dryden and be dedicated to the new instrument package. Upon successful completion of the engineering test flight, the system will be certified as operational and made available for data gathering activities. Additional calibration flights may be available to the investigator if requested and should be coordinated through the NASA Programs Manager.
The integration process is strongly dependent upon the investigator being timely and accurate with the structural and electrical definition of the proposed instrument as well as the interface requirements with the aircraft. The ER-2 operation is staffed by a highly experienced and specialized team of experts who will assist investigators to the best of their ability.