PRIVATE jets for businesspeople to buzz about in come in many sizes. At one end are tiny planes to carry a handful of executives, costing $2m-3m. At the other, an Airbus A380 superjumbo can be kitted out as a palatial corporate headquarters in the sky, with space for dozens of staff to work and rest in comfort, for around $400m. When the financial crisis hit four years ago, business aviation was booming. Globalisation, strong economic growth and the rise of emerging-market multinationals meant there were more companies than ever needing to move important staff around the world quickly and efficiently. But as the global economy stalled, orders slumped - compounded by a backlash against corporate planes in America in 2008, after the bosses of its biggest carmakers jetted into Washington, DC, to ask for handouts. Now the main questions are: when will the industry regain its pre-crisis heights; and will all of the plane makers make it that far? The bad publicity prompted some big American firms to put their private jets up for sale, adding to an overhang of used planes that still compresses the market. The prices of second-hand jets are a third below their peak, and still falling. The makers" combined order books have slumped from around $90 billion in 2008 to about $40 billion now. But analysts at J.P. Morgan think this will at last be the year business jets regain altitude, and that in 2015 deliveries may surpass 2008"s peak of 1,136 planes of all sizes (see chart). Historically, their sales have followed trends in company profits, with a few years" lag - and now profits seem to be on a clear upswing. The biggest, most lavish corporate jets have suffered least in the downturn. Rising commodity prices have allowed a class of super-rich, from Middle Eastern potentates to Russian oligarchs, to splash out on converting full-sized airliners into private jets. But orders for smaller jets have nosedived, forcing Cessna and Hawker Beechcraft, two American firms dependent on this end of the market, to make drastic cuts. On April 2nd Hawker Beechcraft said its losses last year soared to about $482m, from $174m in 2010. Last month the company persuaded creditors and investors to provide $120m to keep it going while it works on a rescue plan. The big six used to be a big five - America's Gulfstream, Cessna and Hawker Beechcraft, Bombardier of Canada and Dassault of France - until Embraer of Brazil decided ten years ago to branch out from making jets for regional airlines. It has continued to launch new models, and this year will start delivering the Legacy 500, an $18m, eight-passenger jet. Gulfstream will be chasing it with its ultra-long-range G650, also due out this year. They will soon face competition from Japan's Honda, which has long dreamed of mass-producing business jets, as it does cars and motorbikes. After years of delays it should start delivering its first model, the six-passenger HondaJet, next year. A bigger threat to established makers, in the long term, is China's state aerospace giant, AVIC, which is determined to be a force in business jets as in all other types of aircraft. As part of its plan to develop a full range of business jets by 2020, AVIC has been buying Western firms with technology and know-how, such as FACC, a German firm that makes parts for Embraer and Bombardier. Last month AVIC agreed on a joint venture with Cessna to build jets in China, and it is working on a similar deal with Embraer. Given China's immense size, strong growth and the expanding global footprint of its big companies, it is not hard to imagine the country one day overtaking America as the biggest market for corporate jets. But for now its airspace remains tightly controlled by the armed forces, and owners of private planes have to fly through a smog of bureaucracy. Other potentially big markets for business jets - from Brazil to Indonesia - are not building enough airports to keep up with demand for flights. So although there are azure skies on the distant horizon, in the short range the airspace is getting crowded with new competitors and new planes, and there may not be enough business to keep them all flying. Hawker Beechcraft has brought in a corporate-turnaround expert, Robert Miller, as its new boss; he insists the firm can survive on its own. But a merger with one of its rivals might make more sense.