In the last year, North Korea has more than doubled the number of training exercises held for its troops. Conspicuously absent from most of these has been large numbers of armored vehicles or warplanes. That's because these fuel-hungry beasts consume more diesel and jet fuel than North Korea can afford. But there has been more North Korean warplanes in the air, indicating that there is growing concern over the decline in flying skill among North Korean pilots.
All this began four years ago, when North Korea, feeling the strain of maintaining one of the largest military establishments in the world (some one million active forces, plus 600,000 reservists, plus an enormous number of people in the militia), began a downsizing program. As many as 20 percent of the 40 reserve divisions were to be disbanded, with troops and equipment redistributed. This reorganization was also meant to deal with the deterioration of weapons and equipment over the last decade, due to lack of use, and resources for maintenance. With fewer weapons to maintain, the limited resources can be applied to keeping more stuff combat ready.
While South Korea adds new weapons and gear each year, North Korean troops get hardly anything, and their aging weapons get older, and less reliable. So the troops will concentrate even more on training that is cheap (infantry exercises). There is very little target practice, because ammo is expensive, and even less mechanized training, because of the cost of fuel and spare parts. But the increased artillery training activity in the last year is partly the result of so much artillery ammo (shells and rockets) reaching the age at which the stuff is too dangerous, and unreliable, to use. So it is fired off in training exercises.
But the importance of flight hours should be a no-brainer. During World War II, when some nations simply didn't have the fuel available for pilot training, they saw combat (and non-combat) losses increase as training-hours-in-the-air went down. Nazi Germany's warplanes began losing, big time, when they could no longer produce enough fuel to allow their trainee pilots sufficient time in the air. This was a trend that had been ongoing since 1942. Up until that time, new German pilots got 240 hours of flying time before entering combat. By comparison, British pilots only received 200 hours and Soviet pilots even less. Germany ruled the skies. But in late 1942, Germany reduced training time to 205 hours. The British now had the fuel, and increased theirs to 340 hours, while the US was providing 270 hours. In the Summer of 1943, the British increased flying time to 335 hours and the US went to 320 hours. At the same time, the Germans reduced it to 170 hours. A year later, the Germans were down to 110 hours, while the British were at 340 hours and the Americans at 360.
This experience was remembered after World War II, and reinforced when, in campaign after campaign, the side with the fewer training hours per pilot, suffered the greatest losses. North Korea, unable to give its pilots much flight time in the last decade, is facing a catastrophic situation if there is a war with South Korea (whose pilots spend more than five times as many hours in the air). Thus the increased flying hours in the last year is more for North Korean pilot morale, than it is to increase North Korea's chances of winning an air war with South Korea.