You can only read here IN FULL about our new Aircraft Carriers what the Defence Secretary, the MOD and the RAF don’t want you to know.
Dear Secretary of State and Colleagues,
Further to my recent email and paper on the “UK response to ISIS Threat”, I now have pleasure in forwarding an educational paper on the Extreme Flight Safety Hazard that will be represented by the F-35B STOVL aircraft attempting to do Ship Rolling Vertical Landings on board Queen Elizabeth class aircraft carriers in all weathers by day and night.
This planned rolling vertical landing procedure will either result in major limitations on the amount of operational flying that can be conducted (additional to the constraints resulting from a ramp fitted deck with no catapult and trap) or, conversely, in major loss of life and equipment – or both.
A major change in course is necessary if our new carriers are to achieve the potential required of them by our national security and defence interests.
With kind regards,
F-35B STOVL Carrier Deck Landing – An Extreme Flight Safety Hazard in its own right: to Life and Limb and Equipment
By Commander Sharkey Ward DSC AFC: One of the only living British military aviators with extensive experience of both Conventional carrier and Harrier carrier deck landings and operations in all weather by day and by night.
The F-35 STOVL aircraft already has insufficient power for it to be able to land vertically on Britain’s new Queen Elizabeth class aircraft carriers in hot/foul weather conditions when carrying expensive stores.
As the aircraft ages, its power/weight ratio will further decrease.
The MoD answer to this most serious problem is for the aircraft to conduct Ship Rolling Vertical Landings (SRVL) instead of Vertical Landings (VL) on board.
In very wet bad weather with serious ship movement in all axes (yaw, roll, pitch and heave), the STOVL aircraft will have very little braking efficiency and much reduced directional control during an SRVL – a recipe for a catastrophic crash on deck or loss of the aircraft overboard.
This paper explains how this is a recipe for disaster and why a change of course away from this aircraft type is essential if we are to avoid loss of life and our new carriers are to achieve any 24/7 strike carrier capability at all.
In poor weather and heavy seas the SRVL can only be described as a most severe and unacceptable Flight Safety Hazard. It will cause the loss of men and machines. People will die and it is ludicrous to suggest it can work as an acceptable procedure.
For the new British Queen Elizabeth class strike carriers to be effective weapon systems in peace, tension or war, their embarked fighter combat aircraft must be able to operate in all weathers by day and night on a 24/7 basis. The old Ark Royal and modern conventional U.S. Navy strike carriers had/have this capability. Britain’s Invincible Class Harrier carriers also demonstrated this capability remarkably well in the Falklands war, 1982.
Unfortunately, we now have the extraordinary situation where a new fighter aircraft is to be embarked in British carriers but this aircraft will not be able to operate in all weathers by day and night on a 24/7 basis. Far from it: in hot/foul weather and/or high sea states it may not be able to operate from the deck at all.
This short paper examines the facts surrounding this appalling state of affairs – that has been created by Ministers listening blindly to the wrong “Messenger”.
It appears certain that our Ministers ignored any representations made to them on the choice of aircraft by the Naval Staff and successive First Sea Lords. Instead, the “Messenger” that Ministers listened to was that of the Royal Air Force (the loudest voice in the Ministry of Defence) who had almost as little carrier operating experience as the Ministers themselves.
It was therefore a clear case of “the blind leading the blind” – and at considerable probable cost to Britain’s future global security and prosperity.
What our Ministers did not realise (because the Royal Air Force conveniently evaded the subject) is that fixed wing deck landing operations are complex and are governed by the elements and deck configuration as much as the capability of the pilot and/or a computer in the cockpit.
Decades of Naval Service experience of Conventional carrier operations as well as Harrier carrier operations have produced vital hands-on expertise and standard operating procedures which, if not followed precisely, can and will result in fatal accidents on deck.
Conventional Take Off and Landing (CTOL)
All weather, carrier borne, fixed wing combat aircraft have been able to operate safely from and to our carrier decks for many decades. Prior to the introduction of the Sea Harrier to naval service all such combat aircraft needed catapult assistance for take-off and arrestor gear for landing.
An angled deck was employed for recovery in order to allow aircraft that failed to catch an arrestor wire to “go round again”. The approach airspeed for such Conventional Take Off and Landing (CTOL) fighter aircraft is approximately 135 kn – which, when the wind over the deck of the carrier is taken into account*, equates to an approach speed relative to the ship of up to 110 kn.
*The carrier steams into the wind to create this wind over the deck.
Vertical and Short Take Off and Landing (VSTOL)
With the Sea Harrier came the ability for the carrier borne aircraft to hover over the deck and then land vertically (in similar fashion to a helicopter). This obviated the need for catapults and arrestor gear (Cat and Trap) and, importantly, did not require the carrier to steam into the wind to generate wind over the deck for the landing. This latter conveyed upon the carrier considerable extra versatility during combat operations or in confined/pilotage waters.
On the downside was the fact that in hot climates (and also with usage/age) available engine power decreased and there was not enough power for the aircraft to land vertically on the deck when carrying expensive ordnance/weaponry – or, indeed, a sensible reserve fuel load. This is the ‘quoted reason’ why the Sea Harrier was withdrawn from service in untimely fashion.
Short Take Off and Vertical Landing (STOVL)
A new acronym, “STOVL”, describes the specified launch and landing procedures that were supposed to be the hallmark of the new fighter aircraft destined for our Queen Elizabeth class carriers.
The carrier-borne F-35B STOVL aircraft has not yet completed development and yet it already suffers from severe weight problems. MOD/DSTL analysis has already demonstrated that, like the Sea Harrier at the end of its service, the F-35B has insufficient engine power (even before it enters service) to allow it to Vertical Land (VL) in warm climates when carrying expensive weapons/stores.
In other words and from square one, the term ‘STOVL’ is a misnomer for the aircraft and our new carriers will not benefit from the considerable extra versatility that would be realised with a full, all weather Vertical Landing capability.
Vertical Landing was the principal and only advantage that the F-35B aircraft had over other aircraft options for the Queen Elizabeth air group. Indeed the F-35B suffers many disadvantages (both operational and fiscal) compared with other CTOL options.
But instead of using common sense and disqualifying the aircraft as a viable strike carrier option because of its lack of engine power, the UK Ministry of Defence decided to adopt an entirely new and untried form of deck landing for the aircraft which supposedly would allow it to return on board at greater weight.
This untried/unproven form of deck landing is known as the Ship Rolling Vertical Landing (SRVL).
Instead of hovering, the aircraft would now maintain a steady forward speed relative to the landing point on deck so that the airflow over the wing provided extra lift to supplement the deficient engine power. Even this acronym is a misnomer: SRVL should read SRL because the vertical component has been removed.
The Ship Rolling Vertical Landing (SRVL)
On land, the Harrier Rolling Vertical Landing (RVL) was used for short air strips and required the pilot to fly a 6° glideslope at 50 kts groundspeed down to touch down. A steeper glideslope made it difficult for the pilot to see the touchdown point under the aircraft nose.
It is likely that the same difficulty will be appreciated in the F-35B. However and unlike the land based RVL, for an SRVL the carrier will have to be steaming into wind to generate wind over the deck.
This raises considerable deck landing and flight safety considerations that appear not have been properly recognised/understood by “The Messenger”, by MoD, by Ministers or by the Naval Staff.
Deficiency in Engine Power Can Only Become Worse
As already intimated and in addition to high-temperature/low thrust considerations, the amount of extra lift required from the SRVL will steadily increase during the life of the aircraft as:
- engine thrust decreases with age and
- aircraft weight increases with in-service modifications/repairs.
The SRVL speed of the aircraft relative to the deck will therefore have to increase making it more dangerous.
Aircraft Speed over the Deck
In low wind/light and variable wind conditions our carriers will only be able to guarantee a wind over the deck of approximately 25 kn (induced by its speed through the water). The F-35B is not as aerodynamically efficient as most of its modern counterparts owing to the unique aircraft configuration – meaning that more speed through the air will be required for a set amount of generated lift.
As the aircraft ages, it is therefore probable that to enable a safe landing with adequate power margins the aircraft will be required to maintain a forward speed relative to the deck of no less than 35 kn – giving an airflow over the wing of 60 kn. This 35 kn touchdown speed will need to increase in very high temperatures, with relatively old engines and/or with basic airframe weight increases. Otherwise the aircraft will not be able to land on board.
But it is not just the speed of touchdown on the deck that can contribute to deck landing problems/hazards. The issues are manifold and the major ones are discussed immediately below.
Intended Touchdown Point on Deck
This must be defined taking into account:
- The position of any new deck landing sight.
- The movement of the ship in high sea states/foul weather.
- The assistance given to the pilot by any new stabilised deck landing sight.
- The amount of braking distance required to bring the aircraft to a halt before it runs out of deck – especially in wet weather.
- The point of no return.
These factors are interrelated and together will define whether a safe SRVL is possible under prevalent environmental conditions.
As with all fixed wing conventional deck landings on board, the flight parameters of the aircraft on the SRVL approach will have to be carefully controlled if the aircraft is to touch down precisely at the intended point on deck.
A defined glideslope will need to be adhered to and air speed must be kept at a defined constant (e.g. 60 kn). A deck landing sight would provide the pilot with necessary glideslope information and this landing sight must be positioned at the desired point of touchdown.
In flat calm conditions, it may be possible for the SRVL to be conducted safely by the “advanced flight control computers”. (Even that is not yet certain.) However, with serious ship motion in heavy seas and a wet, slippery flight deck (over which the flight control computers will have no control whatsoever) the SRVL will remain an Extreme Flight Safety Hazard.
By comparison, the Harrier vertical landing on deck was an easier, much more failsafe evolution than the SRVL in bad conditions.
Our engineers have already claimed technical solutions to various F-35B STOVL problems but many of these claims have proven to be nothing more than wishful thinking, e.g. maintainability of the stealth qualities of the aircraft in the embarked environment; “excellent braking qualities on deck” when de facto the STOVL aircraft’s braking system has been reduced in capability to save weight; etc.
Assurances about SRVL need therefore to be questioned.
In the most difficult conditions, the carrier will be pitching, rolling, yawing and heaving. The point on deck where pitching and yawing have least effect is amidships and this therefore represents the most stable/safest target touchdown point for a SRVL (450 feet from the bow).
This, therefore, is where the deck-landing sight should be positioned. (If the landing site was positioned near to the stern of the ship, it would move up and down with the pitch of the ship – 2° of pitch in the Queen Elizabeth translates to the stern moving up and down 30 feet; which would make the sight totally unusable and the SRVL impossible.)
There will still be ship movement that can be disorientating to the pilot and that can result in an actual touchdown point that is some distance from the intended touchdown point.
For example with ship heave of up to 20 feet (the ship and the landing site bodily moving up and down vertically with sea movement) and using a 6 degree approach angle, this will mean the pilot could land up to 190 feet further down the deck. (20 / tan 6). This would leave a braking distance of only 260 feet before the end of the deck.
The ability of a 14 ton, tricycle undercarriage aircraft (with just three narrow wheels) to brake to a halt on a moving, wet, slippery deck from 35 kn (40 miles an hour) in less than 260 feet must be considered marginal at best – impossible at worst.
Braking capability is reduced further when the ship pitches and/or heaves downwards at or after the moment of touchdown. Essentially the weight of the aircraft is less on the deck, meaning that less braking force can be applied before a skid is induced – the layman will understand this by the feeling that you experience when on a ferry and the floor seems to fall away from you as the ship pitches, or when you are in a lift and it starts to descend.
If the deck is wet this leads to an even lower coefficient of friction – even more braking distance being required.
Aircraft nose wheel steering authority is limited but will need to be applied to counter the rolling motion of the ship (to stop the aircraft sliding over the side or into the ship’s superstructure): so differential braking from each main gear must also be applied. This again reduces the max braking force available.
The erosion of braking distance available through necessary deck-landing site positioning, ship movement, wet weather and, of course, pilot error has been further exacerbated by the designed reduction in F-35B braking capability resulting from the braking system being made lighter as a weight saving measure – to enable vertical landings (which it can no longer do).
The Point of No Return
In poor weather and/or in hot weather there is therefore no doubt/no question that only up to half the carrier’s flight deck will be available for aircraft braking after touching down from a SRVL. And it is clear from the above that perhaps only 260 feet of the flight deck may be available for such braking.
This is a dire circumstance which will demand clear decision-making by the pilot and indeed by the command (whether flying operations are possible or not). The odds are already well set against a safe recovery on board by day and these odds are exponentially increased by night particularly if the landing aircraft only has enough fuel remaining for one single approach to the deck.
In such circumstances and with three or four aircraft airborne returning from a mission for recovery, it is difficult to see how all these craft could be recovered safely without a considerable reduction in mission range/endurance. (The second and subsequent aircraft to land would have to wait until the aircraft ahead has been secured to a flight deck tractor and moved safely out of the way.)
On deck, each pilot will have to make a split-second decision and decide whether he is going to be able to stop safely or whether he will have to eject before sliding over the side or crashing into superstructure or other aircraft parked on deck.
All of the above sounds bad enough by day in a rough sea. Now put that into a night scenario, with low cloud and rain too. Recovering at max landing weights (limited by the available engine power) with unspent stores from a combat mission, perhaps with a cloud base of 200 feet (standard instrument minima) and one has a very ugly situation. With insufficient power available in the F-35B, it is clearly not an acceptable answer to adopt the Ship Rolling Vertical Landing for recovery on board.
Admirals and Air Marshals who have little or no fixed wing carrier operational experience/expertise may misguidedly suggest that “we can make it work” or “we have to make it work”.
That is ‘head in the sand’, wishful thinking at its worst. If the Prime Minister, Secretary of State and colleagues are serious about our national security and power projection capability in defence of our trade routes and energy supplies, they will take note of this expert opinion and configure our new carriers with ‘cat and trap’ and a fully capable fighter aircraft such as the F-35C or, even better, the F-18 Super Hornet family of aircraft.
Unacceptable Flight Safety Hazard
1. In poor weather and heavy seas the F-35B STOVL SRVL can only be described as a most severe and unacceptable Flight Safety Hazard. It will cause the loss of men and machines. People will die and it is ludicrous to suggest it can work as an acceptable 24/7 deck landing procedure.
2. Unless a change in course is made (away from this aircraft and flight deck configuration) preferably at the coming Defence and Security Review, 2015, the Queen Elizabeth class carriers will become a laughingstock with little if any true Strike capability and just a marginal amphibious close air support capability.