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I'm looking at the obstacle chart and the aerodrome chart (pdf; source: Hellenic Civil Aviation Authority) for LGLM (Lemnos, Greece), which serves both military and passenger aircraft.

The runway length is 3016m (9895ft), and, according to the charts, there are also "Arrestor Barriers (nets) 75M before THR RWY 22L", as well as "Arrestor Gears (hooks) 583M, 554M beyond THRs RWY 04R and 22L respectively".

Considering that arrestor gear can have operational consequences for civil aircraft (Skybrary link), apparently its presence is operationally justified for the Hellenic Air Force.

My question is

What could be the reason that arrestor gear is placed on a fairly long runway? The fighters operating from this base are, I believe, F16s and Mirage 2000s. Would a 3-km/10k-feet runway not be enough for such an aircraft, even if we assumed braking problems?

Note: I have been on the island many times as a civil aviation passenger, and the arrestor gear is always in place, so it seems to be a (semi-)permanent installation.

quiet flyer
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2 Answers2

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I can think of 4 reasons:

  1. Pilot Training to use the cable arresting system
  2. Rejected takeoff, fighters don't usually have reversers and may take long space to arrest
  3. Under certain bad runway conditions, like ice, the required landing distance may be very high, and a military airport should work (ideally) under any weather condition
  4. Runway partial unavailability, if part of the runway is unavailable, with an arresting cable system you can still use the other part. This is especially important during a war, when the enemy may damage half of the runway and you don't have time to fix it. Military airports are designed considering also these possibilities.

Source for 3 and 4: https://www.wbdg.org/FFC/AF/AFTTP/afttp_3_32.12.pdf

ocirocir
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  • Good answer, but I would question #1. I can't speak to how Greece trains pilots, but the US Navy doesn't practice field arrestments. – Michael Hall Apr 12 '21 at 17:35
  • Might be worth mentioning that F-16s (used by Greece) have arrester hooks, +1 –  Apr 12 '21 at 23:27
  • @ymb1 AFAIK all F-16s have arresting hooks, as do F-15s. They're not used for landing on a ship but in the event of a brake failure or other issue, they can be used to stop the aircraft. – MD88Fan Apr 13 '21 at 22:02
  • Greece has no aircraft carriers, and V1 (the speed at which takeoff can no long been safely aborted) is calculated in part based on runway length- so absent a brake failure, there’s no reason that an aircraft would overrun on an RTO. – MD88Fan Apr 14 '21 at 00:13
  • @MD88Fan V1 doesn't exist for fighter, at least not the way is conceived in civil aviation. Under certain configurations, the rejected takeoff is not considered and a cable can be your only chance to avoid the ejection. There have been many ejections due to a rejected takeoff. The point 1) was a general consideration not related to the Greek case. – ocirocir Apr 14 '21 at 23:47
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TL;DR: Plenty of modern fighter aircraft are equipped with arresting hooks, why not use them?
Poor runway conditions, i.e. debris, snow/ice, or even rain could be the cause to take a field arrestment. Partial runway availability is also a good reason, in case an aircraft makes an emergency landing due to battle damage or even just a failed engine. Depending on the cause, it may take some time to clear the damaged aircraft from the runway, and fighter aircraft are notorious for their short range, so if there's not a suitable friendly runway within range (perhaps on an island, such as Lemnos), it's preferable to take a field arrestment over ditching the aircraft in the water or ejecting. Pilot incapacitation is yet another reason why this is possible; this YouTube video (

) by C.W. Lemoine, a former USAF and USN reserve fighter pilot (in the F-16 and later the F/A-18), is a good example. Most modern fighters have HUDs, and those often include a flight-path vector marker, which tells the pilot precisely where the airplane is going. A pilot undergoing a physiological episode of some sort, perhaps hypoxia, can simply keep the path vector marker on the threshold of the runway and catch the cable, without having to worry about braking. Given that many modern fighters such as the F-15 and F-16 are equipped with arresting gear, why not use it? It's just another safety tool in the bank to keep pilots alive and airplanes intact.
MD88Fan
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  • I can't imagine good results if a fighter plane should hit a barrier net at 150 kts. – rclocher3 Apr 14 '21 at 00:47
  • @rclocher3: Though your definition of "good" may vary, depending on whether you're the pilot of the plane, or one of the folks driving along the busy highway just off the end of the runway. – jamesqf Apr 14 '21 at 03:51
  • @rclocher3 True, but it generally keeps the pilot alive and the aircraft may be repairable. It's safer than ejecting. In any case, LGLM is equipped with cables just like those on a carrier, so there's no net. – MD88Fan Apr 14 '21 at 12:32
  • @MD88Fan apparently there are both "Arrestor Barriers (nets)" and "Arrestor Gears (hooks)". I don't know what the nets at LGLM are like, but I watched YouTube videos of US naval aircraft hitting the net barricades on aircraft carriers, and I see that those are designed to catch the airframe and not the windscreen, so as not to smash the crew. – rclocher3 Apr 14 '21 at 15:30