Stability derivatives for a delta-wing X-31 aircraft validated using wind tunnel test data
Bibliographic record
Abstract
The calculation and validation of the aerodynamic coefficients and stability deriva- tives for the X-31 model aircraft are the focus of this study. To improve the stability derivative calculations for a delta-wing aircraft in the subsonic regime, a compendium of new methods is programmed into a new code, FDerivatives, and added to the classical DATCOM method. The FDerivatives code is described, as are the improvements achieved in the aircraft canard configu- ration. All the required geometrical data relative to the aerodynamic coefficient estimation of the X-31 aircraft are calculated for the wing-body-tail configuration. Digital DATCOM code was used to validate the geometry and the aerodynamic coefficients, as well as the implicit method and the Jorgensen method. Experimental results are provided for the X-31 model in the low-speed wind tunnel of the German-Dutch Wind Tunnels (DNW-NWB). The FDerivatives code gives very good results in comparison with experimental results. An analysis of longitudinal motion, based on FDerivatives results, is presented at the end.
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How this classification was reachedexpand
Full frame machine prediction
Teacher imitationNot calibrated prevalence, not ground truth. Human validation pending. The Gemma side is a direct model label for every work in the frame, read from the title-only record. The Codex side is a classifier learned from the 10,348 direct Codex labels and calibrated to design-weighted sample rates; fields without enough sample support carry no Codex call. Candidate is the union of the two sides; consensus is their intersection. These outputs are machine_predicted_unvalidated and are not human labels.
Distilled classifier scores by category (both heads)
| Category | Codex | Gemma |
|---|---|---|
| Metaresearch | 0.001 | 0.001 |
| Meta-epidemiology (narrow) | 0.001 | 0.000 |
| Meta-epidemiology (broad) | 0.000 | 0.000 |
| Bibliometrics | 0.001 | 0.000 |
| Science and technology studies | 0.000 | 0.000 |
| Scholarly communication | 0.000 | 0.000 |
| Open science | 0.000 | 0.000 |
| Research integrity | 0.000 | 0.000 |
| Insufficient payload (model declined to judge) | 0.002 | 0.000 |
Machine scores (provisional)
The two teacher heads of the student model, read on this work. A score orders the frame for review; it never asserts a category, and the validation status ships verbatim with every row.
Baseline scores from an immature model (maturity gate not passed, 7 training rounds). Scores rank; they never assert a category.
score_only:v0-immature-baseline · verbatim from the scoring run: score_only means the number may rank works, and no category label ships from itClassification
machine, unvalidatedMachine predicted; a candidate call from one source (direct Gemma or distilled Codex), not a consensus.
How this classification was reached, model by model and score by score, is at the end of the page under "How this classification was reached".