TehnoMil

Sursa: bellflight.com

Aflam lucruri noi, pentru noi, despre UH-1Y:

“The IDAS (Improved Defensive Armament Subsystem) is rated for a 1,000-pound payload; however, the IDAS mounting lugs on the airframe are limited to a weight of 571 pounds. The mounting lug weight limitation inhibited flexibility in configuring mission weapon load outs and did not allow the users to realize the full capability of the IDAS.

For example, during the Offensive Air Support (OAS) missions, the UH-1Y had the power to lift two fully loaded 19-shot rocket pods. The IDAS mounting lug weight limitation restricted the pods to only 11 rockets a piece. If the mounting lugs could support the full capability of the IDAS an additional 16 rockets could be carried, resulting in an increase of firepower from 22 to 38 rockets which would lead to improved support of the Marine on the ground. The IDAS weight limitation also affected the use of external auxiliary fuel tanks. Because of the IDAS mounting lug weight limitation, the 77-gallon tank could not be fully fueled and, therefore, yielded only 4 to 17 minutes more on-station time than internal tanks alone.”

“The small amount of on-station time gained did not offset the loss of weapons stations. Additionally, the external tanks severely reduced the forward and aft depression limits of the crew served weapons and created an obstacle for troops entering and exiting the cabin for assault support missions where troops needed to exit and enter the cabin rapidly. The overall effect was that flexibility was lost during mission planning and mission execution.”

“The new Common Crash Resistant Troop Seat System (CCRTSS) inhibits the ability of the aircrew to close cabin doors. The CCRTSS was designed to attenuate crash g-load, but the larger CCRTSS structure moved seated troops four to five inches farther away from the bulkhead than legacy seating. Missions requiring movement of combat-loaded troops with the cabin doors closed will necessitate removal of the outboard facing transmission seats.
With the cabin loaded in the basic utility configuration of eight combat loaded Marines with seats installed, the crew chief could not fully access and traverse crew-served weapons due to the proximity of the Marines seated next to the door guns.”

Sursa: UH1-Y – Benefits and Deficiencies, Brandon J. Oates

Problemele sint confirmate si intr-un raport pentru Congresul american asupra programului de modernizare al UH-1Y iar la capitolul Recomandari se gaseste o lista lunga de lucruri de rezolvat, unele mai importante, altele mai putin:

The Navy should consider these recommendations for improvement:
Operational Effectiveness

• On a priority basis, replace the rotor blade cuffs to eliminate the maneuvering restrictions at high gross weights and high altitudes. Expand the flight envelope to the required limits.
• Improve weapons delivery accuracy with the Optimized Top Owl system.
• Increase load capacity of mounting point for Improved Defensive Armament System so that the full 1,000 pounds can be carried. For crew-served weapons, the Navy should address the gun depression angle limitation imposed by the Improved Defensive Armament System.

Operational Suitability

• Complete analysis and redesign of rotor cuffs for improved structural integrity, decreased life-cycle costs, and increased aircraft maneuverability. In the interim, improve approaching g-limit warning systems and training in order to reduce focused pilot attention on g-meter during maneuvering flights.
• Improve human factors (neck strain and cord management) of the Optimized Top Owl system and provide a helmet test set and complete documentation.
• Complete electromagnetic environmental effects testing to resolve shipboard compatibility issues.
• Resolve the issue of clearance between the cyclic control and the left seat pilot’s leg.
• Reduce excessive cockpit heat as a result of an expanded avionics suite.
• Address inadequate ballistic eye coverage for the helmet-mounted sight display.
• Improve training and documentation for Optimized Top Owl system procedures, Advanced Memory Unit trouble-shooting codes, and structural repair, schematics, and transportability manuals.

Survivability

• Conduct end-to-end testing of Aircraft Survivability Equipment.
• Test the main rotor gearbox, if an improved version is incorporated, in a full-up system-level test.

Vulnerability Deficiencies

• Redesign of transmission housing.
• Consider self-seal material to full height of fuel cells.
• Ensure adequate self-sealing of fuel bladders per Mil Standard T 27422.
• Consider adding fire extinguishing system as backup to current powder panels in dry bays.
• Add fire suppression/extinguishing system to main transmission bay
• Investigate methods for suppressing/extinguishing fires in oil cooler bay
• Consider adding backup fire extinguishing bottles in engine bay.
• Consider reducing vulnerability of main rotor actuators.
• Consider relocation/redesign of forward flare buckets.
• Exclude combustion products from flares ignited by threat from occupied spaces and flammable materials

Sursa: USMC H-1 Upgrades (UH-1Y)

Intrebarea e daca deficientele au fost rezolvate sau nu, din 2009 pana acum. Pentru ca e bine sa poti inchide usile cabinei sau sa poti folosi mitraliera de bord.

Pana sa avem raspunsul la intrebarea asta, aflam si cum a castigat UH-1Y contractul pentru USMC in locul UH-60:

“The Department of Defense Program Analysis and Evaluation Office initially projected UH-1N upgrades at $11.3 million per aircraft compared to $14.3 million per aircraft for the UH-60 Black Hawk. After initial contracting, the UH-1Y evolved into a new-build program at $19.4 million per aircraft but has survived several program cost reviews because of its 84% commonality with the AH-1Z. The proposed UH-60 Black Hawk currently costs $18.6 million per aircraft and provides robust capabilities across the Marine Corps rotary-wing aviation functional spectrum.”

Sursa: The Multipurpose Black Hawk Utility Helicopter: Rotary-wing Versatility Required for U.S. Marine Corps Enhanced Company Operations, Major Wade J. Dunford, USMC

Daca evaluarea s-ar fi facut comparand cifrele relevante, cele ale elicopterelor noi si nu ale unor modernizari care au fost pana la urma abandonate, UH-60 ar fi castigat si dupa criteriul pretului, pe langa cel al capacitatii de transport (12 vs 8 soldati complet echipati).

Din cauza asta

„În momentul de față Marina SUA e singura care folosește ambele platforme împreună. România e prima țară care a cerut să facă la fel”, a declarat pentru HotNews.ro, Mitch Snyder, CEO-ul companiei americane.”
Sursa: Hotnews.ro, Victor Cozmei.

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