During the display at the Zeltweg airshow in Austria, the Belgian Air Force F-16 suffered a compressor stall that caused a loud bang and an impressive backfire.
On Sept. 3, during its display at the AIRPOWER 2016 airshow in Zeltweg, the “Viper” of the Belgian Air Force F-16 Solo Display Team suffered an apparent compressor stall that forced the pilot to perform a precautionary landing.
Take a look at the footage below. If you jump to 03:20 you will see the aircraft’s engine emanating flames (generating a loud bang you can’t hear) in what seems to be the typical behaviour of a compressor stall.
Compressor stalls (sometimes referred to as afterburner stalls in aircraft with reheat) are not too rare among military aircraft. They can be caused by several factors, including birdstrikes, FOD (Foreign Object Damage), ingestion of turbulent or hot airflow into the air intake etc.
A compressor stall is a local disruption of the airflow in the compressor whose severity may vary from a momentary power drop to a complete loss of compression.
A particular kind of compressor stall is the compression surge that occurs when the hot vapour generated by the aircraft carrier’s catapult is ingested by the aircraft air intake thus creating a breakdown in compression resulting in a the compressor’s inability to absorb the momentary disturbance and to continue pushing the air against the already-compressed air behind it. As a consequence, there’s a momentary reversal of air flow and a violent expulsion of previously compressed air out through the engine intake producing some loud bangs from the engine and “back fires”.
As already explained on The Aviationist in the past, in most of the cases even after suffering a “surge” the compressor will usually recover to normal flow once the engine pressure ratio reduces to a level at which the compressor is capable of sustaining stable airflow.
Some engines have automatic recover functions even if pilots experiencing the surge can be compelled to act on the throttle or, in some cases, relight the engine.
An-12PPS special mission aircraft among those met by the Belgian Air Force “Vipers” during their BAP (Baltic Air Patrol) rotation.
The images in this post were taken by the Belgian Air Force during their latest rotation of support to NATO’s Baltic Air Policing mission.
Flying out of Amari Air Base, Estonia, the Belgian F-16 jets augmented the Lead Nation Spain’s Eurofighter Typhoon jets from January to April 2016.
The aircraft were often launched to intercept and escort Russian planes flying over the Baltics. Among them, Su-27 Flanker, Tu-134AK, Il-76, An-72 and also an An-12PPS.
The An-12PPS “Cub-D” is a jamming variant of the Antonov medium military transport.
According to “Russia’s Warplanes, Volume 1” by Piotr Butowski published by Harpia Publishing, one of the most authoritative sources on Russian-made military aircraft and helicopters today and set to become the standard reference work on the subject, the Russian Air Force operates several standoff ECM aircraft based on the standard An-12 airframe. Their task is to provide jamming cover to formation of transport aircraft carrying airborne troops by disguising the heading and composition of the formation during assault missions behind the front line.
Actually, the RF-90787 “19 Red” depicted in the photos taken by the BAF pilots lacks the most interesting equipment carried by the few An-12PPS aircraft: the Siren-D active jammer, usually mounted in four cigar-shaped pods, two under the forward fuselage and one on each side of the tailfin base. Still, it features another Cub-D’s distinctive feature: the SPS-100 Rezeda self-protection jammer built into the aircraft’s tail in lieu of the tail gunner’s turret.
Indeed, the aircraft is actually a former An-12PPS that was converted to the transport role back in 2001. Still, it’s a pretty rare bird!
A couple of weeks ago, Belgium, Luxembourg, and the Netherlands signed an agreement which is to regulate joint air defense operations carried out in their airspaces.
Signed by the Ministers of Defense of the Netherlands and Belgium, and Luxembourg’s Dutch Ambassador, the agreement, that ratifies that the signing countries will rotate the air policing duties, is a follow-up to a letter of intent signed by the countries back in Oct. 2013 that will have to be ratified by the respective governments, a process that could take about a year according to IHS Jane’s.
The memorandum may be treated as a precedent by other European Union member states, whose air forces, as a consequence of the ever shrinking defense budgets, lack some (basic) capabilities, including the ability to protect the sovereignty of their airspace round the clock.
Anyway, the Benelux countries are willing to begin the joint air space security operation, starting from 2017.
According to the IHS Jane’s report on the issue, the fighter force of Belgium and the Netherlands will defend the countries, providing proper QRA (quick reaction alert) capabilities. Obviously, not only will the defensive operations cover the issue of military threats, but they will also be dealing with renegade aircraft. This means that a new scheme of air policing is to be implemented next year must take every situation into account.
Its legal implications are quite interesting. According to Jane’s, Belgians would be able to ask the Dutch fighters to shoot down renegades in the Belgian airspace and likewise, the Belgian F-16 could be authorized to neutralize such threat in the Dutch airspace.
This is a precedent in the European law, hence additional time is needed to discuss the legal character of the new operation. For example, according to euobserver.com, Luxembourg’s authorities have already excluded any use of lethal force over their territory.
When it comes to Luxembourg, the situation here is quite similar to that of Lithuania. The country has no relevant fighter force, hence help from the neighbors is required to provide air policing.
The situation is also interesting equipment-wise, since the Royal Netherlands Air Force is looking forward to replace its F-16s with the F-35, which will be probably delayed due to the problems related to the Lightning II program. The Belgians are going to replace their F-16s as well. Here the Rafale is a viable candidate, however the joint air policing operations may lead to different choices (including the F-35).
What is more, we can’t help but notice that the joint air-policing initiative is probably aimed at bolstering the Benelux capabilities to deter potential Russian intruders, who so far not only have been active in the Baltic area, but also within the airspace of UK and have often skirted the Dutch airspace.
The aging fleet of C-135FRs, the French variant of the C-135 used as dual-role tanker/cargo and troop carrier aircraft, will be replaced with A400M and A330 MRTT (Multi Role Tanker Transport) aircraft.
Here are some images of Steadfast Noon 2014, a NATO Nuclear exercise.
With news, AIP supplements, comments all over the Internet, and photographs published on aviation websites and spotters forums across Europe, it’s not a secret that, at the end of October, Ghedi airbase, in northern Italy, hosted Steadfast Noon 2014, a yearly exercise whose aim was to train NATO units employing “special weapons” (i.e. nuclear bombs).
Needless to say, such exercises are routinely conducted without the aircraft carrying any bomb, since their purpose is to train the crews to load and unload nukes and to assess the participating units’ ability to safely deal with this kind of ordnance.
In other words, Steadfast Noon exercises and Strikeval (Strike Evaluation) inspections and certifications are extremely important to ensure nuclear weapons can be properly managed should the need arise.
Anyway, in this post you can find some interesting photographs depicting the Steadfast Noon participants, from Poland, Belgium, Germany, Italy, the Netherlands, Turkey, and United States, taken by photographer Fabrizio Berni.