hankb
20th Jul 2008, 11:42
To all Alenia C-27J fans,
here´s the latest on the aircraft´s design flaws, this time it´s the crosswinds limits. The story goes:
Military Plane Crashes in Bulgaria's Varna, Airport Remains Open
8 July 2008, Tuesday
A military transport plane of the Bulgarian Air Force suffered an accident around noon on Tuesday while landing at the civil airport of Bulgaria's Black Sea city of Varna.
As the Spartan C 27 J plane was landing, a strong gust of find from the left caused it to bend to the right. As a result its right propeller hit the ground, and broke.
None of the crew members was killed or injured during the accident. The case is under investigation.
The plane was flying from the city of Plovdiv to Varna. The accident did not interfere with the work of the Varna Airport, which remains open.
Military Plane Crashes in Bulgaria's Varna, Airport Remains Open Military Plane Crashes in Bulgaria's Varna, Airport Remains Open.mht(278KB) (https://webmail.eadscanada.com/exchange/Martin/FWSAR/Competition/C27J/FW:%20Military%20Plane%20Crashes%20in%20Bulgaria%27s%20Varna ,%20Airport%20Remains%20Open.EML/1_multipart_xF8FF_2_Military%20Plane%20Crashes%20in%20Bulgar ia%27s%20Varna,%20Air)
All this comes as no surprise when ones makes the effort to check out their manual.
Section V of the manual, page 5-18, lists the min weight for engine test as 39683 lb because if the aircraft is light, the propwash will cause the wing to become light enough that a crosswind will have an impact.
Further, it reads "If during engine test, the aircraft shows an incipient bank movement, release brakes and bring power to idle." This is because the wing is lifting with the combination of propwash and crosswind, and cutting the engine will drop the wing.
Then, the statement on Crosswind takeoff that states "With crosswind over 10 Kt on takeoff, maximum power must be reached gradually during taxi (rolling takeoff)." As a performance takeoff requires full power against brakes to have shortest takeoff run, they´re concerned that when power has to be added gradually, wing lift and loss of control results.
Page 2-42, states "The aircraft will tend to lift the upwind wing." Thus, when wing lift is added to the requirement for rolling takeoff at crosswinds of 10 knots, you get the above listed incident. .
Lastly, the US C-27A Aircrew training manual (USAF had ten C27A, the G.222 successor which were retired after only a couple of years of service), page 6-43, states "the Copilot must control the aircraft’s lateral attitude with the control wheel, especially during windy conditions."
As the C27J has even more powerful engines than the 222 or 27A above mentioned crosswind challenges will only be exacerbated. A 14 kt crosswind limit for any aircraft this size is ridiculous.
here´s the latest on the aircraft´s design flaws, this time it´s the crosswinds limits. The story goes:
Military Plane Crashes in Bulgaria's Varna, Airport Remains Open
8 July 2008, Tuesday
A military transport plane of the Bulgarian Air Force suffered an accident around noon on Tuesday while landing at the civil airport of Bulgaria's Black Sea city of Varna.
As the Spartan C 27 J plane was landing, a strong gust of find from the left caused it to bend to the right. As a result its right propeller hit the ground, and broke.
None of the crew members was killed or injured during the accident. The case is under investigation.
The plane was flying from the city of Plovdiv to Varna. The accident did not interfere with the work of the Varna Airport, which remains open.
Military Plane Crashes in Bulgaria's Varna, Airport Remains Open Military Plane Crashes in Bulgaria's Varna, Airport Remains Open.mht(278KB) (https://webmail.eadscanada.com/exchange/Martin/FWSAR/Competition/C27J/FW:%20Military%20Plane%20Crashes%20in%20Bulgaria%27s%20Varna ,%20Airport%20Remains%20Open.EML/1_multipart_xF8FF_2_Military%20Plane%20Crashes%20in%20Bulgar ia%27s%20Varna,%20Air)
All this comes as no surprise when ones makes the effort to check out their manual.
Section V of the manual, page 5-18, lists the min weight for engine test as 39683 lb because if the aircraft is light, the propwash will cause the wing to become light enough that a crosswind will have an impact.
Further, it reads "If during engine test, the aircraft shows an incipient bank movement, release brakes and bring power to idle." This is because the wing is lifting with the combination of propwash and crosswind, and cutting the engine will drop the wing.
Then, the statement on Crosswind takeoff that states "With crosswind over 10 Kt on takeoff, maximum power must be reached gradually during taxi (rolling takeoff)." As a performance takeoff requires full power against brakes to have shortest takeoff run, they´re concerned that when power has to be added gradually, wing lift and loss of control results.
Page 2-42, states "The aircraft will tend to lift the upwind wing." Thus, when wing lift is added to the requirement for rolling takeoff at crosswinds of 10 knots, you get the above listed incident. .
Lastly, the US C-27A Aircrew training manual (USAF had ten C27A, the G.222 successor which were retired after only a couple of years of service), page 6-43, states "the Copilot must control the aircraft’s lateral attitude with the control wheel, especially during windy conditions."
As the C27J has even more powerful engines than the 222 or 27A above mentioned crosswind challenges will only be exacerbated. A 14 kt crosswind limit for any aircraft this size is ridiculous.