Unbilled Receivables:	12 Months Ended
Sep. 30, 2015
Unbilled Receivables:
Unbilled Receivables:	5. Unbilled Receivables: Unbilled receivables principally represent sales recorded under the percentage-of-completion method of accounting that have not been billed to customers in accordance with applicable contract terms. Unbilled receivables are $3.9 million and $7.4 million at September 30, 2015 and 2014, respectively and are net of an impairment of $1.3 million in fiscal 2015 and $3.7 million in fiscal 2014. The fiscal 2014 impairment is related to the Delta contract. (See Note 14. Commitments and Contingencies). The Company has negotiated and executed a new agreement in January, 2016 with a customer to provide products and services with current technology. Therefore, the fiscal 2015 unbilled receivable is impaired. We expect that this agreement will also result in the extinguishment of our obligation to deliver certain products under the original contract. The percentage-of-completion method of accounting for EDC revenue, requires estimates of profit margins for contracts be reviewed by the Company on a quarterly basis. If the initial estimates of revenues and costs under a contract are accurate, the percentage-of-completion method results in the profit margin being recorded evenly as revenue is recognized under the contract. Changes in these underlying estimates because of revisions in revenue and cost estimates or the exercise of contract options may result in profit margins being recognized unevenly over a contract because such changes are accounted for on a cumulative basis in the period in which the estimates are revised. Significant changes in estimates related to accounting for long-term contracts may have a material effect on the Company’s results of operations in the period in which the revised estimates are made. Net cumulative catch-up adjustments (loss contracts) resulting from changes in estimates reduced operating income by $117,000, $1.5 million and $444,000 during fiscal years ended September 30, 2015, 2014 and 2013, respectively.

5. Unbilled Receivables:

Unbilled receivables principally represent sales recorded under the percentage-of-completion method of accounting that have not been billed to customers in accordance with applicable contract terms. Unbilled receivables are $3.9 million and $7.4 million at September 30, 2015 and 2014, respectively and are net of an impairment of $1.3 million in fiscal 2015 and $3.7 million in fiscal 2014. The fiscal 2014 impairment is related to the Delta contract. (See Note 14. Commitments and Contingencies). The Company has negotiated and executed a new agreement in January, 2016 with a customer to provide products and services with current technology. Therefore, the fiscal 2015 unbilled receivable is impaired. We expect that this agreement will also result in the extinguishment of our obligation to deliver certain products under the original contract.

The percentage-of-completion method of accounting for EDC revenue, requires estimates of profit margins for contracts be reviewed by the Company on a quarterly basis. If the initial estimates of revenues and costs under a contract are accurate, the percentage-of-completion method results in the profit margin being recorded evenly as revenue is recognized under the contract. Changes in these underlying estimates because of revisions in revenue and cost estimates or the exercise of contract options may result in profit margins being recognized unevenly over a contract because such changes are accounted for on a cumulative basis in the period in which the estimates are revised. Significant changes in estimates related to accounting for long-term contracts may have a material effect on the Company’s results of operations in the period in which the revised estimates are made. Net cumulative catch-up adjustments (loss contracts) resulting from changes in estimates reduced operating income by $117,000, $1.5 million and $444,000 during fiscal years ended September 30, 2015, 2014 and 2013, respectively.