Archive for the ‘Dirty Little Secrets (DLS)’ Category

Fat And Very Unhappy

November 5, 2012

Starting November 1st, officers and NCOs attending U.S. Army Professional Military Education (PME) schools will have to meet all weight and physical fitness standards first. Otherwise, the soldier will not be allowed to attend. This will show up on their record as “failed to achieve course standards.” This will make it difficult, if not impossible, for the soldier to get promoted. If you don’t get promoted within a certain amount of time you must leave the service.

This is the reinstatement of a rule that was suspended during the height of the fighting in Iraq. For the last five years troops could attend PME courses without meeting weight and physical fitness tests. That was because there was a war on and the army could not afford to lose otherwise qualified leaders. But now its peace time and the army can rely more on appearance than reality.

The weight issue has become particularly acute as many troops have undergone multiple, and very stressful, combat tours. While overseas, booze is forbidden, smoking is discouraged, and using illegal drugs will get you tossed out of the service. Prostitutes (and local women in general) are off-limits. What’s left are gyms or workout equipment (in some areas) and lots of food everywhere. Guess what the favorite stress-reliever is. The flab follows you home, as does a lot of the stress. It’s tough being a skinny combat veteran.

This emphasis on thin is one of many similar changes that impose more restrictions on how you can look. That means more conservative haircuts, shaving every day (even when off duty), fewer tattoos, and no visible piercings. Male troops cannot wear earrings at any time. No dental decorations, including gold caps. For female troops this means less makeup and dyed hair as well as shorter fingernails. There will be restrictions on what kind of civilian clothes can be worn on base. There are also a bunch of other petty restrictions, all intended to improve the appearance of the troops.

While fighting continues in Afghanistan, for the lifestyle police in the U.S. Army the war is over. Senior officers and NCOs who were dismayed at the usual wartime relaxation of appearance standards are now talking openly about putting more emphasis on marching and similar drills, as well as greater attention to wearing uniforms correctly and saluting every time you are supposed to. More effort is being directed at improving appearances. On the positive side, there will be growing emphasis on being physically fit, with more soldiers discharged for being too fat or unable to pass the physical fitness test.

But overall, emphasis will shift from being combat ready to appearing (especially to politicians and the media) combat ready. The troops call this “mickey mouse” (or a lot of less printable phrases). The troops don’t like it but the senior officers and NCOs do. This time around the brass promised to change promotion standards to see that more pro-mickey mouse officers and NCOs rise in the ranks. This means going to the right service schools and getting the right assignments, as well as looking and acting like a good soldier should. It’s the old “getting your ticket punched” mentality again.

During wartime the lifestyle police still try to take control but are stymied by wartime realities. For example, back in 2006, the U.S. Army was forced to back off on its “zero tolerance” rules on tattoos. “Zero tolerance” meant that if you had any tattoo showing (when you are dressed, wearing a long sleeve shirt and long pants) the army would not take you. But after turning away so many otherwise qualified recruits the army changed the rule to allow innocuous tattoos to be showing. Moreover, the army didn’t set any precise standards about what was acceptable and what was not. Enforcement was a judgment thing, with recruiters and staff at basic training centers often disagreeing over what was acceptable. The brass had been increasingly allowing recruiters to have the final say. After all, if the guys (and some gals) with visible tattoos, as a group, make good soldiers the tattoo policies themselves may be in danger. But now that fewer proven warriors are required the trend has moved towards appearance. In peacetime this is important because there is no trial by combat to prove who can fight and how well.

The Software Patch Iran Wants To Kill

June 13, 2012

The U.S. Navy has completed work on a new version (3.6.1) of the software for its Aegis BMD (Ballistic Missile Defense) system. A year ago 3.6.1 was successfully tested against an IRBM (Intermediate Range Ballistic Missile), similar to those used by Iran. The IRBM was launched from Kwajalein Atoll (in the Marshall Islands) towards a patch of ocean off the Hawaiian Island, 3,700 kilometers distant. Within eleven minutes of the IRBM lift off, a long range X-Band radar on Wake Island (north of Hawaii) spotted the incoming missile, passed the data to a U.S. destroyer off Hawaii, which calculated the flight path of the target and launched a SM-3 Block 1A missile, which destroyed the IRBM. This was a test of the land based Aegis system that will be built in Europe to protect against hostile IRBMs. That system won’t work without 3.6.1.

The Aegis software upgrade (3.6.1) enables Aegis to track and intercept IRBMs (ballistic missiles with a range of 3,000-5,500 kilometers) as well as quickly share data with other radars. There are numerous other improvements, some of them classified.

This was the 21st successful test of Aegis, which now has an 84 percent success rate in tests. There are other upgrades in the works. Also, last year there was a 3.6.1 test with the new SM-3 Block 1B missile. This was mostly improvements in the final stage of warhead capabilities. While the 1B missile was not a complete success, the 3.6.1 software did what it was supposed to do.

At the moment Aegis anti-missile systems are hot. The U.S. government, encouraged by the high success rate of Aegis SM-3 tests, has been expanding the number of SM-3 equipped ships. With 27 Aegis anti-missile equipped ships in service now, there are plans to have nearly twice as many in the next few years. Nine of these ships will be upgraded to 3.6.1 over the next three years.

Converting Aegis ships to fire anti-missile missiles costs about $12 million a ship, mainly for new software and a few new hardware items. The new 3.6.1 software upgrade costs $50 million. Even with the sharp cost growth this is seen as a safe investment. To knock down ballistic missiles an Aegis equipped ship uses two similar models of the U.S. Navy Standard anti-aircraft missile, in addition to a modified version of the Aegis radar system, tweaked to also track incoming ballistic missiles.

The basic anti-missile missile RIM-161A, also known as the Standard Missile 3 (or SM-3), has a range of over 500 kilometers and max altitude of over 200 kilometers. The Standard 3 is based on the anti-missile version of the Standard 2 (SM-2 Block IV). This SM-2 missile turned out to be effective against ballistic missile warheads that are closer to their target. One test saw a SM-2 Block IV missile destroy a warhead that was only 19 kilometers up. An SM-3 missile can destroy a warhead that is more than ten times higher. But the SM-3 is only good for anti-missile work, while the SM-2 Block IV can be used against both ballistic missiles and aircraft. The SM-2 Block IV also costs less than half what an SM-3 costs.

The SM-3 has four stages. The first two boost the interceptor out of the atmosphere. The third stage fires twice to boost the interceptor farther beyond the earth’s atmosphere. Prior to each motor firing, it takes a GPS reading to correct it’s course for approaching the target. The fourth stage is the 20 pound LEAP kill vehicle, which uses infrared sensors to close on the target and ram it. The Aegis system was designed to operate aboard warships (cruisers and destroyers that have been equipped with the special software that enables the AEGIS radar system to detect and track incoming ballistic missiles). There is also a land based version that Israel is interested in buying and is basically the same one that would be installed in Europe.

Submarines And The Master Geek

June 10, 2012
The U.S. Navy has created a new job category, Information Systems Technician Submarines, and graduated its first class of 16 sailors from the 19 week training course. Before this the growing numbers of PCs on a sub were taken care of by sailors recognized as super geeks and able to do the work in their spare time. But gradually the job became larger and harder. It was finally realized how absurd it was to take care of such a crucial job on an ad hoc basis.

While American subs have had computers on board for nearly half a century, these were, for a long time, only computers that were built into other systems (fire control, sonar, and so on). These were maintained by the specialists trained to care for each particular system. Sailors began bringing their own PCs on board in the 1980s, quickly followed by the more convenient (on a cramped sub) laptops that became abundant by the late 1980s. By the 1990s, the navy was installing PCs as “auxiliary equipment”, but by the 21st century the subs had networks based on PC technology.

Because sub sailors were so highly trained in various technical specialties, most of them were good at fixing PC hardware and software problems. Some of these guys were very, very good at it. But as PC based software began to replace the older custom software for many submarine systems, the PC networks and the PCs that ran them became more complex. This was taking too much time for some of the sailors doing the support. All these guys had other jobs. So the navy finally decided to create a new job category for the master PC geek on each boat. The master geek would not do all the PC maintenance and upgrades but would coordinate it all and keep track of what was done and had to be done. All the other volunteers were still there and, when time allowed, where happy to get involved. After all, for many PC users it’s not just a professional tool but a challenging pastime.

The other military services have also created job specialties that cover PC maintenance and network administration. The navy has also had these jobs for surface ships, especially the carriers. These specialties also include training on defending ship networks against Cyber War attacks.

The 60mm Wonder Got Better

June 6, 2012
The U.S. Army and the U.S. Marine Corps are beginning to receive the new M224A1 60mm mortar. This is an updated version of the original M224. Weighing 16.1-21.1 kg (35.4-47 pounds) the new weapon is a much awaited improvement on pre-M224 models.

For ease of carrying the mortar breaks down into several components. The tube weighs 6.5 kg (14.4 pounds), the bipod is 6.9 kg (15.2 pounds), and the sight is 1.1 kg (2.5 pounds). There are two base plates. The standard one is 6.5 kg (14.4 pounds), the lightweight one is 1.6 kg (3.6 pounds). The older World War II era M2 model weighed 19.05 kg (42 pounds). A less successful World War II era model, the M19, weighed 23.4 kg (52 pounds).

Some of the M224 technology arrived early. Four years ago a new mortar tube was introduced for the 60mm and 81mm mortars. New metals (Inconel 718 alloy) and manufacturing methods (flowforming) reduced the weight of these mortar tubes 30 percent, and increased the robustness. But the lighter tube only reduced the overall system weight about ten percent. The complete M224 system reduced overall weight 20 percent. A year after the M224 was sent to some units for field tests, a few minor tweaks were made, resulting in the recently introduced M224A1.

For the infantry, however, every pound counts. So the M224 was particularly welcome. But the troops were very pleased at how the lighter M224 actually performed.

The marines and the army use the 60mm for infantry companies (each of three infantry platoons, plus a heavy weapons platoon), giving the company commander his own artillery. Modern 60mm mortar shells, which weigh about 1.6 kg (3.5 pounds) each, have a range of 2,000-3,500 meters. For many decades the max range of 60mm mortars was more like 2,000 meters. The M224 can use a longer range (3,500 meters) round. The longer range shells, and the availability of mini-UAVs at the company level, make the 60mm mortar a much more potent weapon. The UAV can spot targets behind hills or buildings and then adjust the mortar fire until the target is destroyed.

Infantry mortars were invented during World War I (1914-18) but have been largely unchanged since then. The current U.S. mortar designs were introduced in the 1980s, but the new tube, longer range ammo, and guided shells (in larger calibers than 60mm) are rather recent developments.

Screw The Americans

June 6, 2012

A court released Hezbollah terrorist leader Ali Musa Daqduq, without trying him on charges of organizing attacks on Iraqi and American troops in Iraq. In 2007, Daqduq was captured by U.S. troops and confessed to training terrorists as an agent for Iran. Hezbollah is a Lebanese terrorist militia founded and funded by Iran. Daqduq was turned over to the Iraqi government last December on the understanding that he would stand trial for his crimes. The U.S. provided lots of evidence for the trial but the Iraqi court released Daqduq for “lack of evidence.” This was apparently done as a favor to Iran and the Iraqis seem to believe that any outrage in the United States will die down before Iraq faces any diplomatic or economic punishment.

Women Join The Crews Of U.S. Boats

June 4, 2012

The U.S. Navy is half way through its program to begin adding women to submarine crews. After two years twelve female officers are serving on two subs, with female contingents for another two subs being trained. The current drill is to have one more experienced (on a sub) female officer (usually a lieutenant or O-3) serve as a mentor for two ensigns (O-1). The second dozen female officers will be integrated to sub life the same way.

Three years ago the Naval Academy was asked to survey its female midshipmen and see how many would want to join the submarine service. About two dozen said they were interested for one of the seven slots the academy has been told would be available. The navy is initially assigning the women to SSBNs (ballistic missile carrying nuclear subs) and SSGNs (four SSBNs converted to carry cruise missiles), mainly because these larger boats have sufficient room to provide separate quarters for women. The Ohio class SSBNs also have hatches large enough to easily get in the equipment needed to build the separate quarters. SSBNs also have two crews, which alternate running the boats on their 77 day cruises. In between each cruise the boats are in port for about 35 days for maintenance and resupply.

One compelling reason for allowing women to serve is a growing shortage of men willing to do so. Four years ago the Naval Academy produced only 92 male officers for submarine duty that required 120. Submariners must be volunteers and satisfy strict physical, psychological, and academic qualifications.

This would not be the first time female naval officers have served on American subs. There were already twelve submarine qualified female officers in the navy when the navy decided to go forward with putting women on regular crew duty. That is, these twelve had taken all the training required for someone to serve on a submarine. There is a lot more training on the boat before you become part of a crew but these women are qualified to serve for short periods. These women were technical specialists and do serve for short periods on submarines, sharing a two person stateroom. The Other navies (Australia, Canada, Denmark, Sweden, Spain, and Norway) allow women to serve on subs but not all of these countries have had many, if any, women actually volunteer for the service.

The U.S. Navy has a unique situation, however, mainly the length of the cruises (even the SSNs, or attack boats, go out for a month or more per cruise). The nations that already allow women on subs have non-nuclear boats that spend far less time at sea each time they go out. The women on these sub crews have got used to the lack of privacy and both genders have adapted, as has been the case with mixed crews on surface warships.

But the wives of American submariners have been openly hostile to the idea of mixed male/female crews and have not been reluctant to make their concerns known. What the wives worry about is, well, sex. They know that this takes place on surface ships with mixed crews and it has caused a few marriages to break up. Service on subs is even more claustrophobic and stressful. And there are far fewer places, compared to surface ships, for a couple to have some clandestine sex. But this sexual activity, even though banned on all USN warships, does happen.

The berthing problem seems to be overrated, as other navies have simply put a curtain or two up to separate the male and female berthing. The officers and senior NCOs have shared rooms, and if women are allowed to serve on American subs, it will be women officers at first because that’s where the greatest shortage is. Not a lot of men are willing to go through all the training and tests to qualify for a job as an enlisted sailor on a nuclear sub and probably fewer women are interested.

Why Russia Has China By The Engines

June 4, 2012
China has long copied foreign technology, not always successfully. One of these unsuccessful efforts is becoming a major embarrassment, to the point where government officials are complaining about it openly. While the Chinese government tries to control news of leadership conflicts, they often allow arguments to go public when it is believed some public debate might do some good. Such is the case with the uneven effort to manufacture military jet engines in China. The basic problem is the inability of the state controlled aviation company (Aviation Industry Corporation of China) to master the most advanced manufacturing and quality control techniques. The problem is the inability of state-run firms to operate as efficiently as their privately owned counterparts in the West. The public debate points to the continued inability to even achieve the lower (than in the West) manufacturing standards of Russia, whose state-run firms (during the Soviet period) were also never able to match Western standards. Some Chinese officials urge privatizing the engine manufacturers, but many others oppose that on political (not wanting to admit defeat) or practical (losing direct control of a key military industry) grounds. Meanwhile, the manufacturing bureaucrats cannot cope, even after many years of effort and much money spent. While some 20 percent of Chinese warplanes now use Chinese made engines, 80 percent do not and that is something the government has not been able to keep secret.In the last decade China has poured much money and leadership effort into developing a jet engine manufacturing capability. The Chinese encountered many of the same problems the Russians did in the beginning. Developing the necessary engine design and construction skills is difficult. But China has several advantages. First, they knew of the mistakes the Russians had made and so were able to avoid many of them. Then there was the fact that China had better access to Western manufacturing technology (both legally and illegally). Finally, China was, unlike the Soviets, able to develop their engine manufacturing capabilities in a market economy. This was much more efficient than the command economy that the Soviets were saddled with for seven decades. But the state owned engine manufacturers have been unable to develop the entrepreneurial spirit that works so well in the West (and other, privately owned, segments of the Chinese economy).

The Chinese consider the locally designed and built J-10 aircraft and WS-10A engine part of the learning process and they do learn from their mistakes. But jet engines for combat aircraft are very complex, and China is encountering more problems than they expected. Solutions have not kept up with new problems.

And then there’s China not wanting, for a long time, to admit that its own engine development efforts have consistently come up short. For example, two years ago China announced that it was replacing the engines in its J-10 fighter, installing Chinese made WS-10A in place of the Russian made AL-31FN. But last year China quietly ordered several hundred more Russian AL-31FNs. No more talk of using the WS-10A on a large scale.

The Chinese claim the WS-10A is superior to the AL-31F, even though the WS-10A copied a lot of the Russian technology. The Chinese say they have improved on that. But those improvements were often things the Russians already had in the works, like increasing the basic AL-31 lifetime from 900 to 1,500 hours and, most recently, 2,000 hours. Meanwhile the Chinese have failed to master some of the basic manufacturing techniques for high-performance jet engines. Recently Chinese officials publicly made an issue of the Chinese company’s inability to master the skills needed to manufacture turbine blades for high-performance jet engines. The reality is that the WS-10A has some serious, and unpredictable, reliability problems, which are becoming obvious. China believes it will be free from dependence on Russia for military jet engines within the next five years, which implies that Chinese engine manufacturers still have a way to go. It may take longer.

For years China has imported two Russian engines, the $3.5 million AL-31 (for the Su-30, and the local clone, the J11 and Chinese designed J-10) and the $2.5 million RD-93 (a version of the MiG-29’s RD-33) for the JF-17 (an F-16 type aircraft developed in cooperation with Pakistan). But in the meantime Chinese engineers thought they had managed to master the manufacturing techniques needed to make a Chinese copy of the Russian AL-31 engine. This Chinese copy, the WS-10A, is part of a program that has also developed the WS-13, to replace the RD-93 as well. While the Chinese have been able to build engines that are durable, they are still having problems with reliability and that’s a killer with fighter jet engines, where failure in combat can be fatal.

Russian sales of AL-31 jet engines to China have surpassed a thousand, with the addition of several new orders in the past year. This is because China wants to expand its fleet of modern jet fighters (J-10 and J-11) and keep pilots in the air often enough to develop and maintain combat skills. That wears out engines faster. Another reason for the continued orders is persistent Chinese difficulties in developing jet engine manufacturing capabilities. China has been especially keen on freeing itself from dependence on Russian high-performance jet engines for its top-line jet fighters. That has not been happening.

With an increase in orders from the Russian Air Force, the Russian manufacturer of the AL-31 has had to boost production this year by over a third. The Russians also appear confident that the Chinese are not going to solve their engine manufacturing problems any time soon. This can be seen in how China openly (and unsuccessfully) protested restrictions Russia wants on the use of AL-31FN engines. Russia wants guarantees that the AL-31FNs will only be used to power Chinese warplanes and that none of them will be disassembled to assist Chinese engineers in perfecting the illegal Chinese clone of the AL-31FN, the WS-10A. China has been stealing Russian military tech for years, especially since the end of the Cold War. Back then Russia could no longer afford to buy new military gear, and it was only orders from China and India that kept many Russian defense firms in business. With many more orders from the Russian military, the Russian manufacturers feel able to play hardball with China. Russia has China by the engines and is squeezing.

To F-35B Or Not F-35B

May 29, 2012
Britain is having second thoughts about equipping its new aircraft carriers with the American F-35B vertical take-off jet. Years of development delays have driven up the price of the F-35B and reduced its performance. Deliveries have, not surprisingly, been delayed. It’s gotten so bad that Britain decided last year to equip their two new carriers with catapults, so they could use the simpler, cheaper, and more reliable F-35C. But now it’s been found that redesigning the carriers for catapults and installing them would cost over $2.5 billion. That’s seen as too expensive in light of the shrinking defense budget. So now that plan is being revised again to bring back the F-35Bs, whenever they do arrive.The Royal Navy is building two new 65,000 ton carriers, to replace the three existing 21,000 ton carriers (one of them inactive and in reserve). The new carriers will carry 24 F-35s each. But these aircraft and the new carriers won’t be in service for another 6-8 years. At this point the F-35Bs and the new carriers are expected to show up at the same time: the end of the decade.

The F-35B, which will replace the Harrier, is a 27 ton aircraft that can carry six tons of weapons and is stealthy. In vertical takeoff mode the F-35B will carry about twice the weapons as the Harrier  and have about twice the range (800 kilometers). The 27 ton F-35B is armed with an internal 25mm cannon and four internal air-to-air missiles (or two missiles and two smart bombs) plus four external smart bombs and two missiles. All sensors are carried internally, and the aircraft is very stealthy when just carrying internal weapons.

The F-35Cs have longer range and carry nearly a ton more of weapons than the F-35B.

F-22 Pilots Protest

May 28, 2012

The U.S. Air Force has sent several (exact number unspecified but believed to be four) F-22 fighters to an air base in the UAE (United Arab Emirates). The U.S. said this was not meant to intimidate Iran but Iran quickly announced that it felt intimidated and that it considered the deployment of the F-22s to be an unfriendly act.

Meanwhile, the air force admitted that several of its pilots declared that flying F-22s was intimidating and they would rather not. The air force is handling this one gingerly. There will be no courts martial, and the air force admits that it has not been able to find the cause of air supply failures on the F-22. This is what has some F-22 pilots upset. Despite this the air force continues operating its F-22s. The decision to keep flying was made because the air supply problems have not killed anyone yet and they are rare (once every 10,000 sorties).

The 14 incidents so far were all cases of F-22 pilots apparently experiencing problems. The term “apparently” is appropriate because the pilots did not black out and a thorough check of the air supply system and the aircraft found nothing wrong. There have been nearly 30 of these “dizziness or disorientation” incidents in the last four years, with 14 of them serious enough to be called real incidents. Only one F-22 has been lost to an accident so far and, while that did involve an air supply issue, it was caused by pilot error, not equipment failure. Twice in the past year the entire F-22 fleet was grounded because of the air supply problems. The 180 F-22s comprise the most powerful component of the air force’s air combat capability and the brass are eager to find out what is wrong.

The air force has already found some problems with the air supply system (too much nitrogen and other contaminants). The main problem was always about something bad in the air supply. But the air does not go bad in any predictable fashion nor does it become bad enough to cause problems for the pilot. So the air force is still looking for causes.

The U.S. Navy had a similar problem with its F-18s. There were 64 incidents from 2002 to 2009, resulting in two deaths. The navy found that the problem was carbon monoxide getting sucked into the aircraft air system (which the navy modified, eliminating the problem). The air force looked into the navy experience to see if there is anything similar going on with the F-22s. No luck. The air force has looked into a lot of potential causes, without a lot of success.

The air force woes began when it appeared that the F-22 might be having a problem with its OBOG (OnBoard Oxygen Generating) system. The U.S. Air Force also checked the OBOGs in F-16, F-15E, A-10, F-35, B-1, B-2, CV-22, and T-6 aircraft as well. Apparently there were no problems there. The air force believed, at one point, that the F-22 problem might not just involve the OBOG.

OBOGs have been around for over half a century. It’s only in the last two decades that OBOGs have become compact, cheap, and reliable enough to replace the older compressed gases or LOX (liquid oxygen) as a source of breathable air for high flying aircrew. Each aircraft, especially the F-22 and F-35, gets an OBOG tweaked for space, weight, or other conditions specific to that warplane design. It’s this custom design that was also closely studied, to find out how the toxins got in.

OBOGs are standard gear now because aircraft have been staying in the air longer (because of in-flight refueling) and carrying enough compressed oxygen has become untenable. OBOGs were the obvious solution to the problem. Since the 1990s, most American military aircraft have replaced older oxygen systems with OBOG. Most Western nations, and Russia, have followed, at least with their latest model aircraft. Most OBOG systems work by using a mineral filter to remove nitrogen from the air taken in to the OBOG and then sending out the oxygen rich air to the aircrew.

USAF Forced To Go Retro

May 25, 2012

The U.S. Air Force has had its budget cut, and one of the items eliminated was money to buy a replacement for its 40 year old UH-1N helicopters. In response the air force is going to refurbish the UH-1Ns for another 30 years’ service. Meanwhile, the U.S. Army and Navy have largely replaced all their UH-1 transport helicopters. Only the Air Force still uses the UH-1, in the form of the twin-engine naval version. The air force has 62 UH-1Ns, used mainly for patrolling the large tracts of land containing ICBM silos. The main difference between the basic UH-1 and the UH-1N was the use of two engines in the latter. This made the five ton UH-1N safer and more reliable, which was the main reason the air force went with this model. The UH-1N could also carry a few more passengers. For the last few years the air force was looking for 93 new helicopters to replace the UH-1Ns. That search failed because new birds that could match the UH-1Ns were too expensive. It’s turned out to be cheaper to rebuild the UH-1Ns.

Nevertheless, the half century old UH-1 (“Huey”) is fading away. Over 16,000 UH-1s were built and over 4,000 were lost during the Vietnam War. Over two thousand UH-1s are still in service. The 4.3 ton, single engine, UH-1 could carry two crew and eleven troops and was the first military helicopter to use gas turbine (jet) engines. This allowed a lighter helicopter to carry more weight. The UH-1 served the army for fifty years, although since the 1990s, most served in reserve units. The twin engine UH-1 was originally developed for the Canadian military and later adopted by the U.S. Navy, Marines, and many foreign countries who were willing to pay a premium for the additional safety of two engines.

Most of the American UH-1s were replaced by the UH-60 in the 1980s. This 10.6 ton helicopter could carry more and was safer to operate. Recently, the 3.6 ton UH-145 was introduced, this replaced the remaining UH-1s in army service.

The UH-1 was actually a military version of a civilian helicopter (Bell 204) design. Both remained in production through the 1980s, with over 12,000 204/205s being produced.

The U.S. Marine Corps still uses the UH-1N. But the marines have a remanufacturing program for them, which will convert UH-1Ns to UH-1Ys. Eventually a hundred UH-1Ns will be rebuilt at a cost of about $4 million each. New rotors, rebuilt airframes, and new electronics will make the aircraft more capable and eventually bring maintenance cost savings of about $14 million per aircraft. Part of this is achieved by installing sturdier and more reliable components. The marines expect the refurbished aircraft to be as effective as the successors to these designs (the UH-60). For the marines this is probably true. Marines don’t have to move their helicopters as far or carry as much, as the army does. So for most jobs the older helicopters, with new engines and electronics, can do the job just as well, without the longer range and greater carrying capacity of the UH-60. Apparently the success of the marine refurbishment program convinced the air force that there was life left in their old, but still useful, UH-1Ns.