Nasa Student Airborne Research Program (sarp) Instrument Integration Session

NASA Student Airborne Research Program (SARP) Instrument Integration Session

Adam Webster July 20, 2009

SARP Instrument Integration Session

Instrument Selection Process Integration preparation typically begins months to in advance of the actual mission campaign Program manager(s) or other sponsoring agencies are typically interested in getting the “most bang for the buck” Feedback is provided to the sponsoring program manager(s) as to what combinations of potential instruments can be accommodated on the aircraft and what combinations result in conflicts, etc. Most campaigns consist of a combination of “heritage” instruments, which have previously flown on the aircraft, and new instruments to the aircraft • Installation requirements of “heritage” instruments are well-defined • New instrument installations require more preliminary thought and planning as to how the instrument can fit and function with the rest of the proposed payload

Instrument Floorplan Development • • • • • • •

Inlets/exhaust locations Window locations Seat locations Cargo room for aircraft spares, etc. Choose appropriate existing ports in the aircraft whenever possible Sometimes perform aircraft mods when absolutely necessary Utilize existing hardware when applicable and available

SARP Instrument Integration Session

ARCTAS Instrument Floorplan, 2008

SARP Instrument Integration Session

Instrument Installation Detail Design Once a basic instrument floorplan is “finalized”, detailed design of new instrument installations begins Most instruments consist of standard (19” rackmount equipment) and one or more non-standard installations Documentation is an integral part of all facets of aircraft operations and the experimental installation design is no exception Typical instrument installation documentation requirements Installation drawings of non-standard installations (i.e., anything besides rackmount equipment) Structural analysis of non-standard installations Modal (vibration) analysis for installations external to the aircraft cabin Equipment rack loading calculation sheets Electrical schematics for heater circuits Flow diagrams for pressurized systems Batteries/UPS datasheets MSDSs for all chemicals, etc. in the instrument or used for maintenance

Provide input to the detailed hazard analysis performed by DFRC safety group Types and controls Basic hazards include lasers, radioactive materials, radio frequency emitters, pressure vessels, compressed gasses, chemicals, cryogens, motors/pumps, heaters, chillers, batteries/uninterruptible power supplies (UPS)

SARP Instrument Integration Session

General Integration Considerations Instrument Integration Design Requires intimate knowledge of aircraft grade fasteners, materials, processes, etc. • National Aerospace Standards • Mil-Spec Standards • Air Force-Navy Standards

Corrosion prevention—material selection and surface finishes Weld design and inspection—when necessary New electrical wiring—non-flammable (usually Teflon-based Mil-Spec wire) Optical window selection based on instrument requirements: fused silica, BK7 (borosilicate crown glass), Pyrex, etc. • Optical window usage is tightly controlled—windows periodically undergo environmental (temperature and pressure) testing to verify structural integrity

Perform EMI test of aircraft and experimenter systems to see potential interference issues Known EMI issues are kept in mind in the floorplan development phase • Antenna locations (i.e., conflicts between GPS antennas and Inmarsat/Iridium satellite communications systems)

General familiarity with aircraft systems and their potential use to experimenters

SARP Instrument Integration Session

3D Design Tools Extensive 3D geometry modeling is used in new installation design Facilitates the ability to anticipate issues in the component manufacture/fabrication/ins tallation processes to streamline the actual instrument integration process Models are directly linked to 2D CAD installation drawings which are required to document installations Models are directly linked to numerical finite element models used in structural and dynamic analyses Used to generate various electronic files used extensively in the manufacturing process

SARP Instrument Integration Session

Stress Analysis Stress analysis is performed utilizing the applicable loads cases for the installation Aero loading (i.e., lift and drag) Inertial loading • Operational loads • Emergency landing loads

Cabin pressure load

3D geometry models are directly linked to numerical finite element models used in the stress analyses to verify structural integrity of the installation under Utilize engineering calculation software to tie analysis documents together with applicable hand calculations, explanation, and discussion

SARP Instrument Integration Session

Modal Analysis Modal analysis is typically performed on installations external to the aircraft Many of the external installations on the DC-8 can be relatively bluntshaped (non-aerodynamic) objects which, in general, create significant vortex shedding in their wakes

Performed in conjunction with a basic vortex shedding analysis to verify that there will be no significant detrimental dynamic loading due to airflow-induced vibration Sometimes also performed on internal installations if vibration is a significant concern to an instrument’s functionality, alignment,

SARP Instrument Integration Session

Legacy Documentation DC-8 is a relatively old aircraft platform and therefore much of the documentation is legacy hand drawings Designed in mid-late 1950’s Built in 1969 Majority of permanent experimental modifications performed ~1987

Literally thousands of drawings (tens of thousands of pages) of legacy hand drawings in archive

SARP Instrument Integration Session

Instrument Integration Process Integration process requires continual communication and coordination with various groups Instrument principle investigators, instrument engineers, technicians, etc. Aircraft operations engineer, ground/maintenance crew, program manager, flight crew Scheduling instrument team arrivals, component procurement and manufacture, etc so that everything comes together in a timely fashion during the actual upload

Various presentations to review boards to acquire approval for flight Engineering Check Flight—performed with minimal aircraft crew onboard Aircraft is flown through its normal flight envelope limits Verify structural integrity of installations Verify there are no adverse dynamic effects on various installations

Also work with potential experiment groups in the development phase of instruments prior to flight selection

SARP Instrument Integration Session

ARCTAS Instrument Upload, Spring 2008

SARP Instrument Integration Session

Questions?