Revenue Recognition	3 Months Ended
Aug. 31, 2017
Revenue Recognition
Revenue Recognition	Note 3 — Revenue Recognition Sales and related cost of sales for product sales are recognized upon shipment of the product to the customer. Our standard terms and conditions provide that title passes to the customer when the product is shipped to the customer. Sales of certain defense products are recognized upon customer acceptance, which includes transfer of title. Under the majority of our expeditionary airlift services contracts, we are paid and record as revenue a fixed daily amount per aircraft for each day an aircraft is available to perform airlift services. In addition, we are paid and record as revenue an amount which is based on number of hours flown. Sales from services and the related cost of services are generally recognized when customer-owned material is shipped back to the customer. We have adopted this accounting policy because at the time the customer-owned material is shipped back to the customer, all services related to that material are complete as our service agreements generally do not require us to provide services at customer sites. Furthermore, serviced units are typically shipped to the customer immediately upon completion of the related services. Sales and related cost of sales for certain large airframe maintenance contracts and performance-based logistics programs are recognized by the percentage of completion method, based on the relationship of costs incurred to date to the estimated total costs. We recognized favorable cumulative catch-up adjustments of $3.8 million during the three-month period ended August 31, 2016 related to changes in estimated profitability of these programs. Lease revenues are recognized as earned. Income from monthly or quarterly rental payments is recorded in the pertinent period according to the lease agreement. However, for leases that provide variable rents, we recognize lease income on a straight-line basis. In addition to a monthly lease rate, some engine leases require an additional rental amount based on the number of hours the engine is used in a particular month. Lease income associated with these contingent rentals is recorded in the period in which actual usage is reported to us by the lessee, which is normally the month following the actual usage. Certain supply chain management programs we provide to our customers contain multiple elements or deliverables, such as program and warehouse management, parts distribution, and maintenance and repair services. We recognize revenue for each element or deliverable that can be identified as a separate unit of accounting at the time of delivery based upon the relative fair value of the products and services. In June 2016, the U.S. Air Force awarded the new contract for the KC-10 Extender Contractor Logistics Support Program (“KC-10 Program”) to a competitor. Our principal services under the prior contract for the KC-10 Program were completed in January 2017; however, we have provided limited services since that date and will continue to do so for an unspecified period of time. Sales for the KC-10 Program during the three-month periods ended August 31, 2017 and 2016 were $11.7 million and $38.6 million, respectively. Gross profit for the KC-10 Program during the three-month periods ended August 31, 2017 and 2016 was $1.1 million and $2.8 million, respectively. Included in accounts receivable as of August 31, 2017 and May 31, 2017, were $10.8 million and $14.5 million, respectively, of unbilled accounts receivable related to the KC-10 Program. These unbilled accounts receivable related to costs we have incurred on parts that were requested and accepted by our customer to support the KC-10 Program. These costs have not been billed by us because the customer has not yet issued the final paperwork necessary to allow for billing.

Note 3 — Revenue Recognition

Sales and related cost of sales for product sales are recognized upon shipment of the product to the customer. Our standard terms and conditions provide that title passes to the customer when the product is shipped to the customer. Sales of certain defense products are recognized upon customer acceptance, which includes transfer of title. Under the majority of our expeditionary airlift services contracts, we are paid and record as revenue a fixed daily amount per aircraft for each day an aircraft is available to perform airlift services. In addition, we are paid and record as revenue an amount which is based on number of hours flown. Sales from services and the related cost of services are generally recognized when customer-owned material is shipped back to the customer. We have adopted this accounting policy because at the time the customer-owned material is shipped back to the customer, all services related to that material are complete as our service agreements generally do not require us to provide services at customer sites. Furthermore, serviced units are typically shipped to the customer immediately upon completion of the related services. Sales and related cost of sales for certain large airframe maintenance contracts and performance-based logistics programs are recognized by the percentage of completion method, based on the relationship of costs incurred to date to the estimated total costs. We recognized favorable cumulative catch-up adjustments of $3.8 million during the three-month period ended August 31, 2016 related to changes in estimated profitability of these programs.

Lease revenues are recognized as earned. Income from monthly or quarterly rental payments is recorded in the pertinent period according to the lease agreement. However, for leases that provide variable rents, we recognize lease income on a straight-line basis. In addition to a monthly lease rate, some engine leases require an additional rental amount based on the number of hours the engine is used in a particular month. Lease income associated with these contingent rentals is recorded in the period in which actual usage is reported to us by the lessee, which is normally the month following the actual usage.

Certain supply chain management programs we provide to our customers contain multiple elements or deliverables, such as program and warehouse management, parts distribution, and maintenance and repair services. We recognize revenue for each element or deliverable that can be identified as a separate unit of accounting at the time of delivery based upon the relative fair value of the products and services.

In June 2016, the U.S. Air Force awarded the new contract for the KC-10 Extender Contractor Logistics Support Program (“KC-10 Program”) to a competitor. Our principal services under the prior contract for the KC-10 Program were completed in January 2017; however, we have provided limited services since that date and will continue to do so for an unspecified period of time. Sales for the KC-10 Program during the three-month periods ended August 31, 2017 and 2016 were $11.7 million and $38.6 million, respectively. Gross profit for the KC-10 Program during the three-month periods ended August 31, 2017 and 2016 was $1.1 million and $2.8 million, respectively.

Included in accounts receivable as of August 31, 2017 and May 31, 2017, were $10.8 million and $14.5 million, respectively, of unbilled accounts receivable related to the KC-10 Program. These unbilled accounts receivable related to costs we have incurred on parts that were requested and accepted by our customer to support the KC-10 Program. These costs have not been billed by us because the customer has not yet issued the final paperwork necessary to allow for billing.