Yemen's air force lost two fighter planes within a week of battling al-Houthi Shiite rebels in the country's remote mountainous north. The crash of a MiG-21 was reported Oct. 2, and a Sukhoi Su-22 crash was reported Oct. 5. Sanaa has insisted that both were the result of technical failure, while al-Houthi rebels claimed that they shot the planes down. Meanwhile, STRATFOR sources in Hezbollah have been quick to claim that their fighters in Yemen shot both aircraft down with Iranian-manufactured Misagh-1 man-portable air defense systems (MANPADS) — shoulder-fired surface-to-air missiles. Naturally, all of these players have reasons for making these competing claims. Sanaa has every interest in blaming the crashes on mechanical failure than on enemy fire. Al-Houthi claims of shooting down enemy aircraft are good publicity and morale boosts for the rebel fighters, whose latest round of revolt has been raging for more than two months. Hezbollah, on the other hand, is serving at the behest of Iran in Yemen and has sent a number of fighters to the tip of the Arabian Peninsula to fight alongside the al-Houthis. By spreading claims of Hezbollah operatives shooting down Yemeni warplanes with Iranian-made MANPADS, the Shiite militant organization and its patrons in Tehran can together demonstrate Tehran's militant proxy reach. But enemy fire is by no means the only plausible explanation behind these aircraft crashes. Yemeni military operations have increased substantially over the past two months, and Yemeni air force pilots do not exactly get a surfeit of flight time. A rapid increase in not only time in the air (which can lead to both human and mechanical fatigue) but combat operations in potentially more complex mission profiles (increasing the room for pilot error) will therefore increase the risk of a major mishap. These pilots are flying low and fast over mountainous terrain to support ground combat operations against guerrilla targets that are not easy to identify from the air. Moreover, Yemeni air force pilots mostly are flying aircraft with designs that date back to the 1950s. There is considerable room for error even with more-experienced pilots in less-rugged terrain. This leaves open the very real possibility that less-experienced Yemeni pilots in more-rugged terrain might literally fly into a mountain. In addition, increased sortie rates will tax ground crews, and attempts to operate older aircraft already in a poor state of repair can quickly raise the risk of technical failures. Though the Hezbollah claims have not been verified, the potential for MANPADS to be employed in the conflict is a significant concern. MANPADS — especially older models like the Soviet SA-7 — have been proliferated widely since the Cold War, creating a ubiquitous threat. The U.S. State Department and Defense Department have worked to track down, account for and better secure existing stockpiles around the world, with considerable success. As a result, relatively few MANPADS incidents have materialized, even though such weapons systems are attractive to insurgent and militant groups. That said, there is a very real risk of MANPADS made in places like Iran, Russia, Serbia, North Korea and China to leak into the gray and black markets or even be supplied directly from sponsor to proxy, as in the case of Iran and Hezbollah. Indeed, Hezbollah is exactly the sort of nonstate entity that may well have considerable stockpiles of MANPADS. There is curiously very little evidence that the group used MANPADS in the 2006 summer conflict with Israel in Lebanon. However, if Hezbollah does have a stockpile of MANPADS in its strongholds in Lebanon's Bekaa Valley, has transported them to Yemen and is using them, it would suggest a game-changer for Sanaa's fight against the al-Houthi rebels. Furthermore, it would raise a broader concern about where else Hezbollah (or more accurately, Iran) might feel compelled to deploy these weapons systems and where else loose stocks could be floating around the region, particularly in hot spots like Afghanistan, Iraq and Lebanon. The Yemeni government — not to mention the surrounding Arab states — is clearly alarmed by the strength of the al-Houthi insurgency. The al-Houthi rebellion has occurred intermittently since 2004. This time around, however, the Iranians are making a statement in Yemen by supporting the rebels and demonstrating that it has the ability to wreak havoc in its Arab neighborhood should it feel provoked. This threat becomes especially critical as Iran is facing rising pressure from Israel and the West over its nuclear program and is preparing for a potential military clash in the Persian Gulf. STRATFOR reported previously that Hezbollah in Lebanon has already held four mourning councils and two burials (one in the Bekaa Valley and one in southern Lebanon) for its fallen fighters in Yemen. Saudi Arabia, already deeply concerned about jihadist spillover from Yemen into the Saudi kingdom and Iran stirring the pot in its backyard, has been the primary financier behind Sanaa's counterinsurgency efforts and reportedly has been directly involved in bombarding Shiite rebel positions along the Yemeni-Saudi border. Egypt, which got a good taste of Iranian meddling within its own borders when a Hezbollah spy ring was uncovered in April
, is also getting more deeply involved in the Yemeni turmoil. An Egyptian delegation led by Foreign Minister Ahmed Abul Gheit and intelligence chief Gen. Omar Suleiman traveled to Yemen on Oct. 5 to observe the situation firsthand before traveling to Saudi Arabia to consult with Saudi King Abdullah. While in Riyadh, the Egyptians and Saudis debated over how to strengthen Sanaa's hand in this fight. According to STRATFOR sources, the Egyptians are pushing for sustained military airstrikes in Yemen's northern Saada province, greater U.S. assistance and replacement pilots for Yemen's air force. The Saudi leadership is expected to consult with the United States on the matter, but efforts already appear to be under way to place more capable pilots in Yemen's combat jets. A number of former Baathist Iraqi army officers, who are deeply involved in Sanaa's fight against the al-Houthis, are in Yemen serving as advisers . STRATFOR sources claim that Yemen and Saudi Arabia are now seeking out mercenaries, particularly from Ukraine, to fly Yemen's Soviet-era MiGs and Sukhois in hopes of regaining the upper hand against the al-Houthis and their Iranian backers in this intensifying proxy battle. But this counterinsurgency is not going to turn on combat aircraft alone. The Yemeni troops on the ground are growing demoralized with every insurgent ambush and are struggling with the basic counterinsurgency challenge of holding cleared territory. Aircraft can help, but there are limitations to air power, especially when attempting to crush an insurrection in rugged terrain that has the added benefit of foreign help.