3.	Aircraft and Aircraft Engines Held for Lease or Sale

(a)	Assets Held for Lease

At December 31, 2017 and December 31, 2016, the Company's assets held for lease consisted of the following.

	December 31, 2017					December 31, 2016
Type	Number owned		% of net book value			Number owned		% of net book value
Regional jet aircraft		13		82	%		12		73	%
Turboprop aircraft		10		17	%		12		23	%
Engines		1		1	%		4		4	%

During 2017 and 2016, the Company used cash of $32,063,100 and $54,357,600, respectively, for the purchase and capital improvement of aircraft. At the time of purchase in 2016, the Company received $17,179,300 of maintenance reserves related to two aircraft; such reserves are reflected as a deduction in the amount of cash used for purchases and related acquisition costs in the investing activities section of the Company's statement of cash flows for the year ended December 31, 2016.

During 2017, the Company sold seven of its assets held for lease and recorded gains totaling $704,100.

In April 2016, one of the Company's turboprop aircraft was involved in an accident and was declared a total loss by the lessee's insurer. The Company received insurance proceeds of $17,640,000 in May 2016 and recorded a gain of $2,146,500.

During 2017, the Company extended the leases for one of its assets held for lease. The Company also leased, and subsequently sold, an aircraft that had been off lease at December 31, 2016.

Eight of the Company's aircraft held for lease were off lease at December 31, 2017, representing 13% of the net book value of the Company's aircraft and engines held for lease. As discussed in Note 13, two of the off-lease aircraft were sold in the first quarter of 2018.

As of December 31, 2017, minimum future lease revenue payments receivable under non-cancelable operating leases were as follows:

Years ending

2018	$	24,743,000
2019		24,641,300
2020		23,003,000
2021		15,901,600
2022		13,944,000
Thereafter		29,447,400
	$	131,680,300

(b)	Assets Held for Sale

Assets held for sale at December 31, 2017 consist of turboprop airframe parts from three aircraft.

During 2017, the Company received $193,100 from the sale of parts and accrued receivables totaling $779,700 for 2017 parts sales, payment for which was received in 2018. Of such amounts, $885,400 reduced the carrying value of the parts and $87,400 was recorded as gains in excess of the carrying value of the parts. During 2016, the Company received $178,400 from the sale of parts, of which $175,300 reduced the carrying value of the parts and $3,100 was recorded as a gain.

During 2016, the Company sold four regional aircraft that had been held for sale at December 31, 2015, as well as a spare engine that had been written down by $246,200 to its net sales price and classified as held for sale. The Company recorded impairment charges totaling $75,000 for two of the aircraft, based on a reduced sale price.