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Cody2 wrote:

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Could a 20 knot bulk merchant ship be fitted with a flight deck, and operate STOBAR type aircraft?  Something similar to the CVE program in WWII, but with modern aircraft and ships.

New Panamax containerships (e.g. Maersk Edinburgh) might do the trick, since they offer enough speed (24+ knots service speed) for STOBAR ops and enough deck space (366m LOA, 49m beam) to accommodate a separate angled deck (~200m x 20m) and take-off ski-jump (~200m x 20m).

You'd nevertheless need to :

1) get the deckhouse and funnel out of the way

2) build a modular structure (something along the lines of what Maersk proposes for its AFSB concept) to accommodate the hangar and such equipment as the arresting gear. Such a structure would have to be strong enough to cope with arrested landings.

A couple more tidbits on the AFSB concept : Link, Link
  

emc wrote:

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Dassault claims that a Mirage 2000 with two IR missiles and internal fuel can take off, no wind, in about 500 m.  They also state that the F-16C and F-18C can, in a similar configuration and conditions, take off in about 460 m and 520 m,  respectively.   This document claims that a 25,000 lb (11,340 kg)  F-104 needs about 4000 ft (1220 m) ground roll to take-off.  Given the F-104's high wing loading and likely low achievable lift coefficient, it was probably the most runway-hungry fighter of its generation.  Modern fighters have both lower wing loadings (and probably higher achievable lift coefficients) and greater thrust to mass ratios than aircraft of the F-104's generation. 

1) HK posted some interesting numbers for the F-15, F-16 and F/A-18 in the other STOBAR thread

2) I finally found the F/A-18 ski-jump paper I was looking for, and will post more details later. To keep it short :

F/A-18 with 6° ramp and max. A/B :
* 640ft ground roll @ 32,800lb T-O weight, 100kt TO airspeed  
* 700ft ground roll @ 37,000lb T-O weight, 99kt TO airspeed

F/A-18 with 9° ramp and max. A/B :
* 385ft ground roll @ 32,800lb T-O weight, 82kt TO airspeed
* 575ft ground roll @ 37,000lb T-O weight, 90kt TO airspeed

3) I'll post the numbers for the Russian Mig-29K and Su-33. I am in the painful process of deciphering a very interesting book on the latter (written in Russian, hence the pain !).

USN ski-jump evaluation with F/A-18 is described in the paper entitled "United States Navy Ski Jump Experience and Future Applications" by Lee, Senn & Clark.

This paper is part of this document (ref. ADA244869), pp.259-273.

Enjoy !

Navy's Tejas fighter revs for take-off
Ajai Shukla / Business Standard / New Delhi Feb 27, 2012, 00:14 IST

The Indian Navy has signalled strong support to the naval version of the Tejas Light Combat Aircraft (LCA), even before the indigenous fighter makes its first flight next month. In New Delhi, on Wednesday, the defence ministry’s apex Defence Acquisition Council (DAC) sanctioned the building of eight Naval LCA aircraft by Hindustan Aeronautics Limited (HAL).

“The eight fighters will be a mix of single-seat fighters and twin-seat trainers. The money for these has also been allocated,” says a senior Ministry of Defence official who was at the DAC meeting.

The Rs 3,650 crore Naval LCA programme was sanctioned in March 2003. Two prototypes are almost complete, the first a twin-seat trainer and the second a single-seat fighter. The eight fighters sanctioned on Wednesday are “Limited Series Production” or LSP fighters. These will be used for flight-testing, a painstaking process that could last two years or more. Once flight-testing is completed, HAL will establish a full-scale production line.

The Naval LCA is a crucial cog in the navy’s expansion and, therefore, in India’s increasingly visible maritime strategy. It is designed to fly from an aircraft carrier, a floating airfield that can project Indian power across the oceans. India has already bought Russian MiG-29K medium fighters to equip the INS Vikramaditya (formerly the Gorshkov) an aircraft carrier acquired from Russia. But another two (and possibly three) indigenous Vikrant-class aircraft carriers being built at Cochin Shipyard Ltd will field the Naval LCA, along with a medium fighter.

With the first of these, INS Vikrant, at an advanced stage of construction in Kochi, the navy is keen that development of the Naval LCA proceeds alongside. Earlier this month, the normally soft-spoken navy chief, Admiral Nirmal Verma, publicly criticised the Aeronautical Development Agency (ADA oversees the LCA programme) for placing the Naval LCA programme on the back burner, while focusing on the air force version of the Tejas.

The admiral’s words have goaded HAL into action. Business Standard has been told that the Naval LCA will take to the air in March, a landmark event for the navy.

“The Naval LCA will definitely fly in March. We are doing ground runs and starting low-speed taxi trials, in which the fighter rolls on the runway under its own power. Then we will do some high-speed taxi trials, in which the fighter will accelerate to take-off speed; but when its nose lifts off the ground, we will slow down without actually taking off. Only after that will the first flight actually take place,” says PV Deshmukh, HAL’s officiating CMD.

The Rs 10,397 crore air force Tejas project has obtained initial operational clearance (IOC), and will soon join the IAF’s fleet. But the Naval Tejas presents additional design challenges, such as being able to take off from an aircraft carrier’s ski-jump after accelerating for just 200 metres. Even more challenging are repeated carrier deck landings, in which a hook on the aircraft snags on an “arrestor cable” on the deck, forcing the aircraft to a standstill in just 90 metres. These landings, in which the fighter slams into the carrier deck at more than 7 metres per second, are often described as “controlled crashes.”

The navy and ADA will extensively test the Naval LCA on land before venturing onto an aircraft carrier at sea. A Shore-Based Test Facility (SBTF) has been created in Goa, which replicates the dimensions and conditions of a carrier deck, including the arrestor and gear that brings the aircraft to a quick halt; and the optical landing system that allows the pilot to “aim” his fighter at the arrestor wire spread out on the carrier deck. After extensive SBTF testing, the Naval LCA will face the crucial challenge of landing and taking off from an actual aircraft carrier.

The navy’s two prototypes and eight LSP fighters will be powered by General Electric GE F-404 engines. Meanwhile, ADA has selected the more advanced and powerful GE F-414 engine for the LCA Mark II. This engine will also power future Naval LCAs. With 15 per cent more thrust, the GE F-414 will be useful in taking off from an aircraft carrier deck.

And finally :

Su-33 (Su-27K / T-10K) particulars :
* empty weight : 43,210 lb / 19,600 kg
* max. internal fuel : 20,940 lb / 9,500 kg
* standard internal fuel : 11,795 lb / 5,350 kg
* max. ordnance load : 14,330 lb / 6,500 kg
* max. AtoA ordnance load : 7,055 lb / 3,200 kg (8 x R-27E + 4 x R-73)
* thrust with A/B : 2 x 28,220 lbst / 12,800 kgp  

Su-33 (Su-27K / T-10K) T-O weights :
* with standard internal fuel : 55,100 lb / 25,000 kg
* with standard internal fuel, 2 x R-27E, 2 x R-73 : 57,320 lb / 26,000 kg
* with standard internal fuel, 8 x R-27E, 4 x R-73 : 61,730 lb / 28,000 kg
* with max. internal fuel, 2 x R-27E, 2 x R-73 : 65,920 lb / 29,900 kg
* with max. internal fuel, 8 x R-27E, 4 x R-73 : 70,990 lb / 32,200 kg

Su-33 (Su-27K / T-10K) with 14.3° ramp and max. A/B :
* 345ft ground roll @ 61,730lb T-O weight
* 345ft ground roll @ 65,290lb T-O weight with 7kn WOD 
* 640ft ground roll @ 70,990lb T-O weight with 15kn WOD

source : Su-33 Naval Saga by Andrei Fomin, Moscow 2003 (in Russian)          

This other artice might also be relevant to this discussion (emphasis added) :

UK to extend rolling carrier landing research for JSF
Flight International, 21 August 2008

The UK Ministry of Defence is continuing research to refine a hybrid shipboard rolling vertical landing (SRVL) technique, potentially to be employed as the primary recovery mode for Lockheed Martin F-35B Joint Strike Fighters operating from the Royal Navy's two Future Aircraft Carriers (CVF).

A programme of MoD-sponsored research work, including technical advice from the Defence Science and Technology Laboratory (Dstl), has already concluded that SRVL would offer a significant increase to the F-35B's payload "bring back", without any fundamental platform or safety issues. However, further investigations are planned to address a range of optimisation and integration issues, says Martin Rosa, JSF technical co-ordinator in the Dstl's air and weapon systems department.

An SRVL involves a short take-off and vertical landing aircraft performing a "running landing" on to the carrier flightdeck, using air speed to provide wingborne lift to complement engine thrust. The touchdown position on an axial flightdeck is similar to that of a conventional carrier - about 45m (150ft) from the stern, but no arrestor gear is required, as the aircraft uses its brakes to come to a stop within a distance of 90-150m. The technique could allow an F-35B to recover with an extra 907kg (2,000lb) of weapons and fuel, or reduce propulsion system stress and increase engine life.

The Dstl began work to examine the feasibility of employing the SRVL manoeuvre in the late 1990s. Following a series of simulation-based studies, the MoD's investment approvals board in July 2006 endorsed the requirement as part of its F-35B-based Joint Combat Aircraft programme.

Speaking at the Royal Aeronautical Society's International Powered Lift conference in London in July, Rosa said SRVL studies have shown that "a way forward exists to achieving operationally useful increases in bring-back, compared to a vertical landing, on board CVF with an appropriate level of safety". But "uncertainties remain in terms of the scope of an operational clearance and the potential impact on the sortie generation rate for CVF".

Qinetiq used its VAAC Harrier testbed to perform representative land-based flight trials and a ship-based SRVL demonstration aboard the French navy's aircraft carrier Charles de Gaulle last year.

Rosa said past work has also identified a promising visual landing aids (VLA) concept optimised for SRVL and stabilised against deck motion. "We will continue to mature the SRVL-optimised VLA arrangements, look at the possible 'tuning' of the JSF flight-control laws, and further study the effect of SRVL on the CVF sortie generation rate," he said. The capability's full scope will be confirmed after flight trials from the 65,000t vessels, which are due to enter service in 2014 and 2016, respectively.

Other forthcoming work includes optimisation of the approach profile, agreement on the optimal post-touchdown technique, and mitigation for failure cases, such as a burst tyre on touchdown.