Results of the J-5 Marco dynamic similar model flight tests program

Bogdański

et al. 2021

AEAT

Self Cite

Purpose According to the study of the space flight market, there is a demand for space suborbital flights including commercial tourist flights. However, one of the challenges is to design a mission and a vehicle that could offer flights with relatively low G-loads. The project of the rocket-plane in a strake-wing configuration was undertaken to check if such a design could meet the FAA recommendation for this kind of flight. The project concept assumes that the rocket plane is released from a slowly flying carrier plane, then climbs above 100 kilometers above sea level and returns in a glide flight using a vortex lift generated by the strake-wing configuration. Such a mission has to include a flight transition during the release and return phases which might not be comfortable for passengers. Verification if FAA recommendation is fulfilled during these transition maneuvers was the purpose of this study. Design/methodology/approach The project was focused on the numerical investigation of a possibility to perform transition maneuvers mentioned above in a passenger-friendly way. The numerical simulations of a full-scale rocket-plane were performed using the simulation and dynamic stability analyzer (SDSA) software package. The influence of an elevator deflection change on flight parameters was investigated in two cases: a transition from the steep descent at high angles of attack to the level glide just after rocket-plane release from the carrier and an analogous transition after re-entry to the atmosphere. In particular, G-loads and G-rates were analyzed. Findings As a result, it was found that the values of these parameters satisfied the specific requirements during the separation and transition from a steep descent to gliding. They would be acceptable for an average passenger. Research limitations/implications To verify the modeling approach, a flight test campaign was performed. During the experiment, a rocket-plane scaled model was released from the RC model helicopter. The rocket-plane model was geometrically similar only. Froude scales were not applied because they would cause excessive technical complications. Therefore, a separate simulation of the experiment with the application of the scaled model was performed in the SDSA software package. Results of this simulation appeared to be comparable to flight test results so it can be concluded that results for the full-scale rocket-plane simulation are also realistic. Practical implications It was proven that the rocket-plane in a strake-wing configuration could meet the FAA recommendation concerning G-loads and G rates during suborbital flight. Moreover, it was proven that the SDSA software package could be applied successfully to simulate flight characteristics of airplanes flying at angles of attack not only lower than stall angles but also greater than stall angles. Social implications The application of rocket-planes in a strake-wing configuration could make suborbital tourist flights more popular, thus facilitating the development of manned space flights and contributing to their cost reduction. That is why it was so important to prove that they could meet the FAA recommendation for this kind of service. Originality/value The original design of the rocket plane was analyzed. It is equipped with an optimized strake wing and is controlled with oblique, all moving, wingtip plates. Its post-stall flight characteristics were simulated with the application of the SDSA software package which was previously validated only for angles of attack smaller than stall angle. Therefore, experimental validation was necessary. However, because of excessive technical problems caused by the application of Froude scales it was not possible to perform a conventional test with a dynamically scaled model. Therefore, the geometrically scaled model was built and flight tested. Then a separate simulation of the experiment with the application of this model was performed. Results of this separate simulation were compared with the results of the flight test. This comparison allowed to draw the conclusion on the applicability of the SDSA software for post-stall analyzes and, indirectly, on the applicability of the proposed rocket-plane for tourist suborbital flights. This approach to the experimental verification of numerical simulations is quite unique. Finally, a quite original method of the model launching during flight test experiment was applied.

Section: Methodsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Results of simulation and scaled flight tests performed on a rocket-plane at high angles of attack

Kwiek

Bogdański

et al. 2021

AEAT

Self Cite

“…UAVs were used for flight testing to save resources, but a manned research vehicle test is also envisaged in the future. The approach was taken, as the research team has extensive experience in the design and testing of UAVs serving as dynamically similar flying models (Galinski et al, 1997;Goraj et al, 2012;Goraj and Szender, 2004;Goraj and Szender, 2005). The project was conducted by a consortium of four entities: Warsaw University of Technology, the Air Force Institute of Technology and Marcin Szender MSP under the leadership of the Institute of Aviation which is eyeing the subsequent project behind I-31T (Piwek and Wisniowski, 2016;Iwaniuk et al, 2016).…”

Section: Introductionmentioning

confidence: 99%

Wind tunnel tests of the inverted joined wing and a comparison with CFD results

Krysztofiak

Miller

et al. 2018

AEAT

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Purpose The purpose of this paper is to present the methodology and approach adapted to conduct a wind tunnel experiment on the inverted joined-wing airplane flying model together with the results obtained. Design/methodology/approach General assumptions underlying the dual-use model design are presented in this paper. The model was supposed to be used for both wind tunnel tests and flight tests that significantly drive its size and internal structure. Wind tunnel tests results compared with the outcome of computational fluid dynamics (CFD) were used to assess airplane flying qualities before the maiden flight was performed. Findings Extensive data about the aerodynamic characteristics of the airplane were collected. Clean configurations in symmetric and asymmetric cases and also configurations with various control surface deflections were tested. Practical implications The data obtained experimentally made it possible to predict the performance and stability properties of the unconventional airplane and to draw conclusions on improvements in further designs of this configuration. Originality/value The airplane described in this paper differs from frequently analyzed joined-wing configurations, as it boasts a front lifting surface attached at the top of the fuselage, whereas the aft one is attached at the bottom. The testing technique involving the application of a dual-use model is also innovative.

“…Experiments described in this paper were undertaken to establish if it is possible to predict the dynamic behaviour of the full‐scale aircraft when some numbers of similarity criteria are not matched. To reach this goal a scaled RPV was built (Galinski, 1996; Galinski et al , 1997) equipped and tested in flight (Plate 1). This was a copy of the J‐5 Marco motorglider (certified in 1986).…”

Section: Introductionmentioning

confidence: 99%

Experimental and numerical results obtained for a scaled RPV and a full size aircraft

Aircraft Engineering and Aerospace Technology

Goraj

2004

Self Cite

This paper describes a series of tests of remotely piloted vehicles (RPV) and full scale aircraft from which most of the performance information and selected dynamic characteristics normally required for aircraft operation can be obtained. The main goal of the paper is to compare corresponding characteristics of RPVs and full scale aircraft and establish if RPV testing can help and influence an early stage design project in order to optimise its aerodynamic configuration and predict its static and dynamic characteristics. This paper presents basic similarity transformations, including mass scale, force scale, power scale, linear acceleration scale, Reynolds number scale etc. as functions of linear scale. It was found that tests in steady conditions are difficult to perform, time‐consuming, and do not offer significant advantages over the classical wind tunnel tests. RPV tests in unsteady conditions are much easier to perform and quite accurate.