Experimental Measurements of Passenger Ride Quality During Aircraft Wake Surfing

Abstract

Center completed a series of research flights to better understand the challenges of aircraft wake surfing using civilian airplanes and commercial avionics. Airlines and air cargo carriers have identified uncertainty about increased passenger/crew discomfort due to noise and vibrations as a potential obstacle to the widespread adoption of aircraft wake surfing. To measure the effects of wake surfing on passenger ride quality, NASA instrumented a business jet with cabin noise and vibration sensors. The airplane was then flown under control of an experimental autopilot at multiple locations within the wake of a similar airplane. This paper presents a summary of the measurements collected on those flights, an assessment of passenger discomfort correlated with wake surfing performance benefits, and qualitative evaluations collected from passengers aboard during the research flights.

Experimental Measurements of Fuel Savings During Aircraft Wake Surfing

“…As discussed in Ref. [12], the onset of wake-induced cabin vibration consistently occurred near 3.5-percent fuel flow reduction. As seen in Fig.…”

“…This paper presents an evaluation of the fuel flow measurements taken during the seven wake surfing test points on the final flight and the associated tare points. See Reference [12] for an analysis of the effects of wake surfing on passenger discomfort during this experiment.…”

Whole-Body Vibration Experienced by Pilots, Passengers and Crew in Fixed-Wing Aircraft: A State-of-the-Science Review

“…During calm flight, a weighted vibration dose value equivalent to 1.07 m/s 1.75 per hour (data normalized to 1 h from reported results for a 10 h flight), measured at the seat mounting point was reported for a NASA Gulfstream G-111 test aircraft. This increased to 1.57 m/s 1.75 per hour when flying in turbulent air [21]. Modelled data predicting the vibration at the seat base for an Airbus A320 reported values from 0.11 m/s 2 r.m.s.…”

“…The external environment includes ground conditions when taxiing, taking off and landing [16][17][18], air turbulence [19], and the effects of wake from other aircraft [20]. Intentional 'surfing' the wake and wingtip vortices of a leading aircraft can increase lift of a trailing aircraft; therefore, this reduces fuel burn, resulting in improvements in range, economy, and emissions [21].…”

Modelling and Control of an Urban Air Mobility Vehicle Subject to Empirically-Developed Urban Airflow Disturbances

“…The ISO 2631 standard was chosen because it provides both quantitative values for acceleration for various discomfort levels and provides accelerations that are potentially hazardous to ones health. This standard has also been used to asses passenger comfort in large passenger aircraft [33][34][35]. Figure 1 shows the health guidance caution zones in weighted acceleration.…”