Wood Material Characterization for Dynamic Impact Simulation of Tu-154M Wing with Birch Tree

On April 10, 2010, a Polish Air Force Tupolev Tu-154M (registration 101) crashed near Smolensk North Airport in Russia, killing all 96 people on board. The official investigation, summarized in the MAK report, attributed the accident to pilot error under conditions of severely reduced visibility during approach.
NIAR was subsequently contracted to conduct an independent numerical analysis of the accident, with two specific objectives: first, to evaluate the structural damage predicted by a finite element model of the Tu-154M against the damage documented in the MAK report; and second, to assess the survivability conditions of each occupant by comparing the injury outcomes derived from the simulation against the known injuries reported in the investigation record.

The crash involved a collision with a birch tree, which meant that for a structural reconstruction to accurately proceed, a thorough wood characterization campaign had to be conducted, covering both physical testing and simulation. Wood is not exactly what one expects to be researching in an aircraft institute, but by that point I had learned that NIAR's project portfolio operates on the principle that if the investigation demands it and the facilities can support it, the work gets done regardless of how far outside the domain it lands. Wood was unusual, but it was not the strangest material we ever characterized. That distinction belongs elsewhere, and involves skin and bone, which is a story for another entry.
What I had also learned by then was to embrace the learning curve as a structural feature of the work rather than a quirky punctual circumstance, and to treat a rigorous literature review as the actual foundation of every claim. The full team was involved in the FE reconstruction and verification, but the wood investigation itself was concentrated within my immediate group. I had the good fortune of working alongside D. on the birch tree identification, sourcing, mechanical testing, simulation, and the development and study of the MAT_143 material card. It consumed roughly a year of focused effort, run concurrently with my PhD qualifier preparation and coursework in theory of plasticity, and it remains among the work I am most proud of.
The project also surfaced a question that was raised but never formally resolved: whether the findings from these contained sub-investigations, particularly material characterizations conducted for a specific contract, should be published independently given their potential broader value. The literature review made the case starkly: the intersection of rigorous material characterization and wood is thin, and the available scholarship rarely delivers the level of detail required to construct a fully parameterized, generically applicable wood material card for simulation. The gap was real and consequential.
Given my lack of prior experience with wood and the curiosity that tends to follow me into every new domain, the project pulled me into the world of woodworking well beyond the lab. I spent time with local Wichita practitioners ranging from hobbyists and tradespeople to artists who treat wood as a primary medium, partly for the project and partly because I could not help myself. None of them had any awareness of what finite element analysis could offer in terms of predicting failure regions, guiding joinery decisions, or estimating the longevity of a given design in a given species, but several were immediately receptive to the idea when it came up, including to the notion of paying for material characterization of their wood of choice alongside a simulation-informed design review.
One person in particular made that entire side of the investigation possible in a way that goes beyond acknowledgment in a project report. Kody Ramsey opened his workshop without reservation, fielded an unreasonable volume of fired-up questions with patience and generosity, gave me something no textbook or material database could: a genuine feel for wood as a physical material with character, grain, resistance, and memory. That kind of grounded, tactile knowledge turned out to matter in ways that showed up directly in how we approached preparing the specimens, clamping conditions and simulation work. Most importantly, that unassuming, funny, kind, and dedicated man casually told me, as if merely seeking confirmation, what was arguably my greatest scientific epiphany of 2019: wood is among the most extraordinary and statistically improbable materials in the observable universe. Supernovas, comets, asteroid belts, and planets are abundant with minerals, heavy elements, and even exotic compounds, but wood requires biological life and a specific evolutionary emergence of plant tissue, a biochemical architecture that arose only once in Earth's own history. No planet yet discovered has shown any evidence of conditions capable of generating anything close to wood.
In addition to that, Kody was immediately receptive when the idea of simulation-informed design came up, to the point of genuinely considering paid material characterization of his preferred wood species alongside a design review, which made the market gap visible even from within a crashworthiness lab. It proved to me, once more, that intersectionality in science is a practical virtue, that overspecialization uncoupled from genuine curiosity about radically different ways of knowing and making is a form of intellectual impoverishment, rather than curation, and that science in the service of people is at its most meaningful.