In the past few years, investors have snapped up shares of master limited partnerships in the energy industry in search of high-yield stocks with tax benefits. But the stunning fall in crude oil prices over the past two months is wreaking havoc on companies with significant oil interests. This is endangering the dividend payouts from many MLPs.

Fortunately, it's still possible to seek out a high yield without trying to catch falling knives in the energy sector. Aircraft leasing firm Aircastle (NYSE:AYR) offers a solid 4.3% dividend yield, has a manageable payout ratio, and its shares look quite cheap. Investors looking for high-yield stocks should think about adding Aircastle to their watchlists.

What does Aircastle do?

Aircastle is a value-oriented aircraft leasing firm. It invests in aircraft that it believes are selling for less than their intrinsic values. Aircastle sometimes holds these planes through the end of their useful lives, but also looks to opportunistically sell them when resale prices are attractive.

Traditionally, Aircastle has specialized in mid-life-cycle aircraft, buying planes that were five to 10 years old. More recently, it has started to invest in planes that are fewer than five years old in order to reduce the risk of obsolescence given that Boeing and Airbus are in the midst of introducing a slew of new, fuel-efficient models.

Aircastle sources many of its planes from other aircraft leasing firms that specialize in newer aircraft. Other times, the company participates in sale-leaseback transactions with airlines or buys planes that airlines are looking to get rid of.

Many airlines prefer to lease aircraft for a variety of reasons.

Aircastle leases these planes to a wide variety of airline customers: 61 carriers scattered across 37 countries. Airlines often prefer to lease aircraft rather than buying them in order to manage their own balance-sheet risk and fleet flexibility or to get access to better financing.

Strong earnings and modest valuation

As of third quarter 2014, Aircastle's net cash interest margin -- the difference between lease revenue and financing costs as a percentage of net book value -- was 9.9%, up from 9.6% a year earlier. Net cash interest margin is a key indicator of profitability for aircraft leasing firms, and current trends appear favorable for Aircastle.

The two biggest inputs to net cash interest margin are lease rates and interest costs. Aircastle's credit rating is improving, which is giving it access to cheaper financing. Earlier this month, the company issued $500 million of unsecured debt due in 2022 at a 5.5% interest rate. This will allow it to finance planned growth investments at a modest cost.

Meanwhile, Aircastle will benefit from the recent drop in fuel prices -- unlike high-yield stocks in the energy industry. As of Sept. 30, 2014, its average aircraft age was 8.6 years, with an average remaining lease term of 4.9 years. In a low-fuel-price environment, those planes will be more valuable when they come off lease than they would have been with oil at $100 per barrel.

Low oil prices could make Aircastle's aircraft portfolio more valuable.

Analysts currently expect Aircastle to post EPS of $1.50 for 2014, rising to $1.99 in 2015. As of Friday's close, the stock was worth $20.10: just a little more than 10 times projected 2015 earnings. Aircastle also looks cheap in that it trades at a slight discount to its book value.

A high-yield stock suited for tax-advantaged accounts

Unlike many other high-yield stocks, Aircastle has a very manageable dividend payout ratio. Its current quarterly dividend of $0.22 -- or $0.88 annualized -- amounts to less than 60% of its projected 2014 EPS and about 44% of its projected 2015 EPS. This provides plenty of future dividend growth potential.

Like many other high-yield stocks (including REITs and MLPs), Aircastle is structured to minimize corporate taxes. The company is officially registered in Bermuda, which allows it to keep its effective tax rate very low. However, this means that its dividends are taxed at ordinary income rates rather than the reduced rates of "qualified" dividends.

As a result, Aircastle stock is a good candidate to be held in tax-advantaged accounts where this income tax can be avoided or deferred. (However, you should consult with a tax professional with regard to your personal tax situation.) For example, I hold my Aircastle shares in a Roth IRA.

Aircastle is thus an attractive alternative to MLPs for investors seeking high-yield stocks. In the short run, it will be a big beneficiary of the drop in oil prices, while in the long run, it should be able to ride the wave of growth in the global aviation market. Meanwhile, Aircastle stock trades at a very reasonable valuation and has a sustainable dividend. What's not to like?