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A photometric study of the Near Contact Binary (NCB) system V609 Aql revealsit to be the westernmost star of a close double, with brightness variations andimplied parameters more extreme than those derived in an earlier photographicstudy, in which images of the variable and companion were almost certainlyblended. The system's brightness variations exhibit deep primary eclipses($\delta$ V = 1.04) and secondary eclipses ($\delta$ V = 0.44) matched to amodel fit with a derived orbital inclination of i = 84.8$\pm$0.2 degrees andestimated component spectral types of F8-F9 and K2-K3. The primary overfillsits Roche lobe in the optimum eclipse solution, inconsistent with thedefinition of NCBs. Period changes in the system are studied from 23 publishedtimes of light minimum and 21 newly-established values: 18 from examination ofarchival Harvard plates, and 3 from ASAS data and new CCD observations. O-Cvariations from 1891 to 2007 exhibit a long-term parabolic trend indicative ofa period decrease, dP/dt = -(7.75$\pm$1.39) x 10^-8 d/yr, corresponding to masstransfer to the secondary of (6.5$pm$1.2) x 10^-8 SM/yr. Superposed variationsmay indicate fluctuations in the mass flow. The system is estimated to be ~513pc distant.

New Insights Into the Nature of the Eclipsing System V609 Aquilae