RAF suspends Typhoon flights after finding ash deposits

Southsider1

http://news.sky.com/skynews/Home/UK-News/Volcano-Ash-In-RAF-Jets-Engines-As-UK-Passenger-Flights-Return-To-Normal-Levels/Article/201004415612624?lpos=UK_News_Carousel_Region_0&lid=ARTICLE_15612624_Volcano_Ash_In_RAF_Jets_Engines_As_UK_Passenger_Flights_Return_To_Normal_Levels

bringitdown

http://news.bbc.co.uk/2/hi/uk_news/8637978.stm

The CAA also says conclusions should not be drawn from the RAF's statement about the air-worthiness of civilian aircraft.
It adds that the all-clear for civilian aircraft to return to the skies still stands and there have been no reports of any ash damage.

Nope!

Steyr

http://www.flightglobal.com/articles/2010/04/22/341024/ash-cloud-raf-suspends-typhoon-flights-after-finding-ash-deposits.html

Aircraft
DATE:22/04/10
SOURCE:Flightglobal.com

RAF suspends Typhoon flights after finding ash deposits
By Craig Hoyle

Royal Air Force Eurofighter Typhoons are the latest military aircraft to have been confirmed as having sustained possible damage during Europe’s volcanic ash crisis.

"A small number of Typhoon fast jets were found yesterday [21 April] to have volcanic ash deposits on them following routine post-flight inspections," the Ministry of Defence confirms. "As a precautionary measure, non-essential flying has been temporarily suspended, pending the outcome of further checks and analysis.” Operational tasks, such as quick reaction alert cover, "have not been affected and continue", it adds.

The service had previously restricted flight activities with the type to only QRA cover during a six-day period while non-restricted airspace was closed across much of Europe. However, training sorties resumed yesterday with the Typhoon, which is powered by two Eurojet EJ200 turbofan engines.

Finland’s air force has already released images of the effects of ash ingestion on the engines of one of its Boeing F-18 fighters which had been airborne on 15 March. Lockheed Martin F-16s from a NATO operator, believed to have been the US Air Force, were also affected, according to comments attributed to a senior US diplomat.

Flightglobal’s MiliCAS database says the RAF has now taken delivery of 62 Typhoons from the UK’s Tranche 1 and Tranche 2 production orders for the type. The fleet is based at RAF Coningsby in Lincolnshire, with several aircraft also currently deployed to the Falkland Islands.

andy_g

Already been posted by styer in regards to the RAF typhoons.

Threads merged

ian_m

I'm very curious to know if commercial airlines are checking for deposits. Have any new procedures been implemented for checking? And has any airline noted anything unusual about engine behaviour?

The public would be the last to know because airlines don't want to lose any more money.

Celtic Mech

For anyone unfamiliar with Aircraft Engines....Engines that are in the likes of Fighter Jets - When air is sucked in the front of the engine then 100% of that air is used internally by the engine (Be it combustion or cooling process of Turbines etc) . In comparrisson if we take a regular aircraft such as the Airbus A320 or Boeing 737, each equipped with CFM 56 series engines. The Fan at the Fron of the Engine draws air in BUT only approx 20% of that air is actually going to go thru the Core of the Engine (i.e. thru both comprerssors, combustion chambers then turbines), the remaining 80% of the air is what is called Bypass Air.
Therefore from the above, it would be my opinion that volcanic ash of the same concentration/density would harm a Fighter jet more than a passenger aircraft. Its just my 2 cents.

highlydebased

Celtic Mech wrote: »

For anyone unfamiliar with Aircraft Engines....Engines that are in the likes of Fighter Jets - When air is sucked in the front of the engine then 100% of that air is used internally by the engine (Be it combustion or cooling process of Turbines etc) . In comparrisson if we take a regular aircraft such as the Airbus A320 or Boeing 737, each equipped with CFM 56 series engines. The Fan at the Fron of the Engine draws air in BUT only approx 20% of that air is actually going to go thru the Core of the Engine (i.e. thru both comprerssors, combustion chambers then turbines), the remaining 80% of the air is what is called Bypass Air.
Therefore from the above, it would be my opinion that volcanic ash of the same concentration/density would harm a Fighter jet more than a passenger aircraft. Its just my 2 cents.

I was going to say that myself.

Absurdum

so the brits are ripe for an air-led invasion are they?

Fratton Fred

I get the bit about military engines being affected worse than commercial ones, but what about props? Why were Flybe and Aer Arran grounded?

andy_g

Fratton Fred wrote: »

I get the bit about military engines being affected worse than commercial ones, but what about props? Why were Flybe and Aer Arran grounded?

There a turboprop aircraft so basically a jet engine with a prop stuck to the front. easiest way to describe it

Mr Benevolent

andy_g wrote: »

There a turboprop aircraft so basically a jet engine with a prop stuck to the front. easiest way to describe it

The reason TPs are affected is because they are low-bypass engines. All the air goes through the engine, not just 20% of it.

derry

I cant go with that small core versus big bypass logic

A tubine engine with a prop or large bypass fan or a milatary version with only a small core motor will all have small cross section of air that will enter the fuel burning combustion chamber .Its in the fuel burning core the majority of the damage takes place .The ash melts in the burn of the fuel and then sticks to cooler parts of the fuel burning core and solidifies and often blocks the cooler fuel supply rings that inject colder fuel into the engines.

If ash density in the air is low it will take a longer time for the ash to block up the engines.
If ash density in the air is high it will take a shorter time for the ash to block up the engines.

Sounds to me like the solution the airlines have opted for is strip down repair more frequently the turbine engines and clean off the ash collection

I saw that if you use you car in a high ash density region say like close to volacno with lots of ASH expect to replace the oil every ~150 miles instead for ~10,000 miles .Also expect to replace or clean out the air filter every 150 miles.

So I supect same for airlines replace more engine stuff while there is ash to enter engines

Derry