????亞馬遜金牌會員的特權正在變得越來越神奇。亞馬遜（Amazon）上個月宣布，他們將與美國郵政總局（U.S. Postal Service）合作，開展周日送貨服務。上周日，他們又公布了一項公司兩日送達服務的升級擴展版：利用遙控無人駕駛飛機的30分鐘送達服務。

????亞馬遜首席執行官杰夫?貝佐斯在哥倫比亞廣播公司（CBS）的節目《60分鐘》（60 Minutes）里向記者查理?羅斯透露了亞馬遜研發實驗室的最新成果：兩架擁有無人機系統（UAS）的小型八旋翼直升機。它們可以在用戶下訂單后的30分鐘內，直接從亞馬遜龐大的物流中心網絡中提貨，送到用戶的家門口。貝佐斯表示，這項服務被稱為“Amazon Prime Air”，最快在2015年就能推出，不過也許還要稍長一些的時間來解決技術難題。

????貝佐斯在訪談中對羅斯表示：“想要實現這項服務，最大的難題在于向美國聯邦航空管理局（FAA）證明它的安全性。我不希望有誰覺得它已經指日可待了。從現在開始，我們還需要幾年的加倍努力。”

????然而，現實不會這么簡單。目前來看，即便是亞馬遜已經研發的這種無人機也無法在操作員的視線之外運行，而美國聯邦航空管理局也尚未說明需要作出哪些改變才能放寬限制。此外，即便是這些小型無人機——它們只有5到10磅重——也只有半個小時的電池續航時間，最高端的無人機可以支持45分鐘到1個小時。而當它們的負載量增加時，電池續航時間還會進一步縮短。這是個巨大的技術難題，一直限制著小型無人機的應用。

????然后，美國聯邦航空管理局將會對它的安全性和可靠性提出大量質疑，而小型無人機制造商需要對此進行證明，包括選擇在自己的研發實驗室中開發無人機的亞馬遜。一名公司代表在給《財富》（Fortune）郵件中表示，除去在《60分鐘》中展示的模型之外，實驗室中還有其他幾種技術模型。所以比起貝佐斯上周末給全球展示的樣品，最終的產品也許看起來會有一些不同。

????貝佐斯表示，樂觀估計時間會更長一些，比如四年或者五年，如此一來，聯邦航空管理局和亞馬遜都有時間找出辦法，確保這樣的系統安全運轉。在2012年聯邦航空管理局的《現代化與改革法案》（Modernization and Reform Act）中，美國國會授權聯邦航空管理局開放國家領空，允許包括民用和商用的小型無人機的使用。（現在只有經過特別授權的政府和學術機構可以在美國領空使用無人駕駛飛機，而商用無人機仍被禁止。）????????????

????The perks of an Amazon Prime membership just keep getting curiouser and curiouser. Amazon (AMZN) -- which announced just last month that it is teaming with the U.S. Postal Service to begin making Sunday deliveries -- late Sunday unveiled a further augmenting of the company's two-day delivery service: 30-minute delivery via unmanned, autonomous drone aircraft.

????During a segment airing on CBS's 60 Minutes, Amazon CEO Jeff Bezos revealed to correspondent Charlie Rose the latest development out of Amazon's R&D lab, two small "octocopter" unmanned aerial systems (UAS) designed to pick up and carry packages directly from Amazon's sprawling network of fulfillment centers directly to customers' doorsteps within 30 minutes of the user placing an order. The service -- called "Amazon Prime Air" -- could debut as soon as 2015, though it will likely take a bit longer to iron out the technical challenges, Bezos said.

????"The hardest challenge in making this happen is going to be demonstrating, to the standards of the FAA, that this is a safe thing to do," Bezos told Rose during the segment. "I don't want anybody to think this is just around the corner, this is years of additional work from this point."

????The reality is not so simple, however. Right now even small UAS like the ones being developed by Amazon cannot be operated outside of line of sight of the operator, and the FAA has yet to say what would have to change for that requirement to be lifted. Further even these small UAS -- which can weigh as little as five to 10 pounds -- have a limited battery life in the half-hour range, with 45 minutes to an hour being at the very high end. That battery life is further reduced as the payload grows heavier, creating a difficult technical challenge that continues to hamstring small UAS applications.

????Then there's the larger questions of safety and reliability that will have to be addressed first by the FAA and then demonstrated by small UAS manufacturers, including Amazon, which is opting (at least for the time being) to develop its UAS fleet itself within Amazon's R&D labs. There are several prototypes in the lab beyond the one demonstrated on 60 minutes, a company rep told Fortune via email, so the future might end up looking quite a bit different than the one Bezos unveiled to the world last night.

????An optimistic estimate is more like four to five years, Bezos said, which should grant both the Federal Aviation Administration and Amazon time to figure out just exactly how such a system would safely work. Under the FAA Modernization and Reform Act of 2012, Congress mandated that the FAA open up U.S. national airspace to small drone traffic, including for civilian and commercial operators. (Right now only specially authorized government and academic institutions can fly UAS in the national airspace, and commercial use of UAS is prohibited.)????????????