Vertical panic

The thick crowd of hardcore F-35 critics are out in force in the last while regarding supposed "problems" with the F-35B vertical landing, which, according to some well known "no-F-35" commenters, deny the achieving of the expeditionary operations that are at the base of the STOVL requirement.
It has been sad to read articles in which long-time aviation commenters wake up to AM-2 mat with a few long decades of delay; and it is sad to see how they ignore how forward basing operations are actually conduced, in order to lament "issues" with the program.
I don't think most of the above commentators actually ignore the facts: i believe they are deliberately using half-truths to launch new attacks against the programme that they effectively hate. For some well known characters, the F-35 is now an obsession. They launch attacks at each and every chance they get, regardless of facts.

US Marines preparing a strip with AM-2 mat. The AM-2 has been in use for many decades, and in Afghanistan alone, 8 million square feet of mat have been deployed.

The current "storm" has started when it was officialised that the F-35B won't display its vertical landing capability at the RIAT and Farnborough air shows in July, because the runways at the two airports pose safety challenges due to the high temperatures connected with a vertical landing or take off.
The problem, specifically, is that the high temperature exhaust directed on the concrete runway are highly likely to provoke spalling, cracking the superficial layer of concrete and thus potentially creating a FOD issue.
I don't know if in future, following more exhaustive testing, the F-35B will more freely land vertically at air shows, but what i know for sure is that this "issue" was known already a long time ago, but no one really cared because it has no real operational impact at all.
We are not producing F-35Bs for air shows, but for operations on warships, on short and austere runways and on expeditionary airfields. And all of these things can be done, because the F-35B can actually land and take off vertically on ship decks and on AM-2 matting, which are the surfaces from where it should do so. The F-35B has completed well over seven hundred vertical landings, most of which have been made on two landing pads built of AM-2 matting at Patuxent River.
Most importantly, it can make short take offs and short rolling landings on runways and other hard surfaces.

Vertical landing is used mostly just for shipboard operations. Forward basing ashore does not necessarily require vertical landing, and when vertical landing is required, it is tipically done on matting surfaces laid down specifically to create landing pads. This has been the rule for decades, already with the Harrier: it is not something introduced by the F-35.
It is true, the F-35B generates more heat and twice as much thrust as the Harrier, so the need for matting is even more marked than with the old AV-8B. But this is the price that we have to pay for a STOVL jet that has to be supersonic and able to land vertically with a very substantial bring back weight.
Vertical bring back has been another capability of the F-35B that has been widely attacked in the past, but it is actually one of the most impressive features of the aircraft. At 5000 lbs, it is just 1000 lbs less than the aircraft carrier bring back weight for the F/A-18 Hornet, and it is well above the bring back of the Harrier itself. Before the latest variant of the Pegasus engine was rolled out, the Harrier's bring back weight margin was truly minimum. When the british Harrier GR7 flew over Sierra Leone in 2000, the bring back was limited to one 540 lbs bomb plus fuel margin, and that was when flying without external fuel tanks. The bring back weight margins in hot weather were, in other words, incredibly tight.
Sea Harrier and Harrier operations in the Persian Gulf on the Invincible class carriers in the late 90s was subject to limitations, and were assessed as being doable only between November and April, as the high ambient temperatures limited engine take off and landing performance.
Even with the latest Pegasus engine variants, the bring back weight of the Harrier remains very limited, and at least 2000 lbs short of the F-35B's margin.

Weight requires thrust, and thrust means heat. It is actually quite brilliant how the F-35B does not need re-heat for VTOL, and the lift fan, despite its drawbacks, is actually a very smart solution as it generates cold air lift. Without these two features, if all the lift force had to come from high temperature jet exhaust, the F-35B would probably really melt the deck.

Returning to the focus of the article: is there a VTOL problem negating forward basing or at least requiring a dramatic change from Harrier procedures honed over decades of operations?
The answer is no, because the key ability for forward basing ashore is short take off and landing, not so much the vertical. Where vertical landing is expected, there will be landing pads built with matting. It has always been so, already with the Harrier. A few examples:

RAF Germany during the Cold War. The Harriers, initially based at the vast Wildenrath air base, then
moved to Gutersloh, were operated according to the WARLOC concept. WARLOC stands for War Locations, and it was a plan to advance packages of Harrier aircraft onto six forward, pre-surveyed locations within the 1(BR) Corps area of responsibility.
Six more flying sites were earmarked as step-ups, and two logistic parks held the supplies needed to make the pre-surveyed sites operational.
At the start of the conflict, the HQ RAFG would have ordered to stand up the six forward bases (two for each Harrier squadron in the force) and the convoys of personnel and supplies would have rushed forwards to these locations. The Harriers in the meanwhile would have taken off from their Main Base (Wildenrath first, Gutersloh after 1976) for their first attack missions, before landing at the forward sites, completing the dispersion plan.

The forward sites would  have been requisitioned under emergency legislation. The Harrier would have used country and urban roads built to schnellweg standard, meaning that they had integral cycle tracks on the shoulders of the carriageways, making them perfectly sized to act as short runways.
Main roads and autobahns (motorways) were not considered for Harrier basing, as they would be needed for land convoy movements and for much larger emergency airfields for non-STOVL aircraft.
The Harrier was meant to fly CAS sorties from the forward sites, without external fuel tanks to maximize the load of weapons (tipically BL755 cluster bombs and/or SNEB 68mm rockets). No 4 Sqn also had a tactical recce role, and had a five-cameras pod in its arsenal.

We have to make one thing clear here: the famous airstrips in the woods that we see in photos of the Harrier force in Germany were training sites with a possible but unlikely war role. They were not the actual War Locations. Wartime operations would have happened exploiting stretches of secondary roads in countryside villages and towns, so to have paved surfaces from which to make short take offs and landings.
The use of locations carefully selected within villages  offered the added benefit of buildings to exploit for the accommodation of supplies, personnel and communications. Supermarkets and other suitable large buildings would be exploited for parking the aircraft away from sight.
It is obvious that the Harrier force could not train for this exact scenario: some exercises were made flying from stretches of suburban roads temporarily closed by german authorities for that purpose, but the training was actually made in the famous woodland camps.
Here, the personnel lived in tents and on vehicles when lucky, and the aircraft operated most of the time from grass strips, something which made the sight of bogged-down Harriers quite common, giving much work to air support Royal Engineers. Temporary matting and metal planking was used as possible to help the aircraft move around without sinking in mud. Each of these woodland forward bases had a vertical landing pad built typically with MEXE (the british Military Experimental Establishment mat), and sized 75 feet x 75 feet. The Harriers would land vertically on the pad tucked away in a clearing in the forest, and from there they would be towed by Unimog 4x4 vehicles onto the well camouflaged parking areas.

Thankfully, a number of representative training areas was obtained during the 70s using stratches of paved roads in the Sennelager training area. The actual intended War Locations, however, were secrets well kept. The Harrier Plans office would send out teams in civilian clothes to carry out discreet surveys of promising locations identified by air reconnaissance. The main requirement of the forward sites was a stretch of paved road measuring at least 500 x 10 meters, with suitable access from "operational areas". These would tipically be light industrial estates or supermarkets: in other words, any kind of building accessible from the road and suitable for hiding aircraft and site infrastructure.
Note the desired size of the to-be landing strip: short take offs with considerable weapon loads and short landings were the key, not vertical landing. Harrier could have probably landed vertically on parking lots and other paved surfaces, yes, but this was not indispensable. Even repeated Harrier vertical landings, although less stressful than F-35B's VLs, would have a damaging effect on such surfaces, so that the lay down of a pad of matting might have been needed eventually.

An F-35B comes in to land on one of two AM-2 mat pads in Patuxent River. Much of the testing has been done here: the pads have seen hundreds of vertical landings, and several vertical take offs.

Belize 1975 and afterwards. Belize's single airport, despite the ambitious "international" title, only had a single, relatively short runway (considering the rigours of the climate) which was unsuitable for any combat aircraft of the RAF other than the Harrier. Six No 1 Sqn Harriers were deployed to Belize in a hurry with Victor air tanker support in response to very real threat of invasion coming from Guatemala. An earlier Belize emergency had been tackled in 1972 by rushing the aircraft carrier HMS Ark Royal across the Atlantic to deliver a show of force with its Buccaneers, but in 1975 Guatemala visibly prepared for a new aggression, and this time Ark Royal was too busy to move, as she was part of NATO' Northern Flank defence plan, and was engaged in exercise Ocean Safari off the north norwegian coast.
The Harrier deployed forwards to the small, inadequate airport, and operated there for four months. Operation NUCHA, as the deployment was known, eventually ended when Guatemala was rattled by a fearsome earthquake on 4 february 1976, which put the country in such distress than it ceased to be a threat.

Guatemala again mobilised its army already in 1977, however, and in July that year the UK again sent the Harriers, as Ark Royal was once more unavailable. The mighty Ark was about to reach the end of her operational life, and the UK no longer had assured availability of aircraft carrier power as her sisters had been sacrificed to budget cuts. In its absence, the Harrier detachment in Belize became permanent. It remained in place for sixteen years. Once more, the key aspect of forward basing capability was the ability to take off and land on short strips, not the ability to land fully vertically.


Falklands and the Atlantic Conveyor. In the Falklands the Harrier was used in innovative ways on hastily refited ships such as Atlantic Conveyor and on land, where it made use of a really barebone forward base established ashore after the amphibious landing in San Carlos.
The Atlantic Conveyor, a mixed RoRo and container cargo ship, was given a large deck by steel-plating the openings of the container holds, and on the bow, a vertical landing pad was assembled, using matting treated with anti-skid material. The pad can be easily seen in the photos of the vessel going south. The pad allowed the Harrier to fly on board from Ascension, and it was then used to allow the aircraft to take off from the vessel to fly the short hop to the aircraft carriers, when the Conveyor reached the area of operations.
Loaded back in the UK or flown in from Ascension, the Atlantic Conveyor eventually transported eight Sea Harriers, six Harrier GR3s, six Wessex helicopters and four Chinooks.
During the 10-days transit from Ascension to the area of operations, one Sea Harrier was kept ready on the pad, to be launched to intercept any shadowing argentine aircraft that might come spying the movements of the british vessels. The Harrier GR3s were bagged up to protect them from the salty marine environment.

The Vertical pad on the bow of Atlantic Conveyor

The constant here is the landing pad: it might be a logistic complication, but it is necessary from well before the F-35B appeared. Its installation, however, allowed the VTOL aircraft to fly in and away from the hastily converted merchant ship. Although no QRA Interception was launched from the Conveyor as no shadowing aircraft was detected, being able to even mount a QRA on the vessel is an example of the flexibility that the Harrier, and in future the F-35B, offer.

Sea Harrier and Atlantic Conveyor launch pad

The Atlantic Conveyor also transported all the equipment to build an Harrier Forward Air Base ashore, which was to include vertical landing pads and a 400 meters runway, plus fuel infrastructure and command and control sufficient to base and operate a squadron of 12 aircraft.
Unfortunately, the sinking of the Conveyor dealt a very vicious blow to the plan, as much of the precious equipment needed for establishing the FOB sunk with her. Nonetheless, enough planking and matting equipment of all sorts was recovered to put together a 260 meters strip, a vertical landing area and space for parking and servicing 4 Harriers. The FOB, although far more austere and barebone than intended, gave the Harrier GR3s a place were to mount Ground Alerts from which they could quickly move out to deliver air support. The Sea Harriers coming from the carriers far out at sea, away from argentine attacks, had the chance to use the FOB to refuel and extend the duration of their vital CAP patrols up-threat.
As barebone as it was, the FOB would support peaks of 120 air movements per day, delivering tens of thousands of litres of fuel every day.
The landing strip offered the bare minimun facilities needed to land and refuel, and its limits were shown in some occasions: one Harrier GR3 was lost when it overshot the end of the strip after a FOD incident. The thrown-together pieces of matting of different sorts could not lock together as well as they should, and the downwash of the famous Chinook Bravo November caused some of the planking to shot out of place.


In that occasion, while the FOB was hastily repaired, two Sea Harriers which urgently needed fuel were to accomplish another famous feat, being diverted to away from the FOB to land vertically on the flight deck of the LPDs HMS Fearless and HMS Intrepid instead.
The F-35B would be able to replicate these feats, operating from strips of matting (the test fleet makes regular use of a short expeditionary strip of AM-2 matting at Patuxent River) and also making non-standard vertical landings and take offs (with light load) on ships such as LPDs.
The heat of their exhaust would impose greater wear and tear on such flights decks, but it would be possible. Actually, in the case of the USMC, the F-35B would likely encounter little to no problems on amphibious and support shipping decks, as these are set to receive modifications (including most likely Thermion coating where necessary) to deal with the heat and stress generated by the MV-22 Osprey, which is being cleared to land on or at least to vertically replenish most ship types in the US fleet.

Vertical heat panic reporting actually began with the MV-22 Osprey. But the USN is working to clear the MV-22 for landing on many platforms, and for vertically replenishing many others. Many of these decks would probably be fine for emergency landings.

In the Falklands war, after the ceasefire, an air base was urgently stood up in Port Stanley, and Sea Harriers and Harrier GR3s mounted guard from both the runway ashore and from the carriers, with HMS Illustrious relieving Hermes and Invincible.
Even when the runway was repaired and extended to allow the arrival of the Phantoms of the Royal Air Force, the Harrier GR3s maintained a presence on the islands, to be ready to operate in case a surprise attack or problem of any sort were to deny the runway. They only left in May 1985, when the completely new Mount Pleasant air base was opened, ensuring a solid basing arrangement for conventional fighters.



Desert Storm. USMC AV-8B Harriers exploited the STOVL capability of the aircraft to deploy on the beat up landing strip at King Abdul Aziz, a naval base on the North Eastern coast of Saudi Arabia, immediately behind the positions of the 1 MEF force of marines holding the defensive line at the border. The runway was long but not well kept, and there was a near complete lack of support infrastructure, and the USMC and Seabees were hard at work to assemble a vertical landing pad of 150 x 150 feet, plus a 72 feet wide taxiway parallel to the strip, again made with AM-2 matting, and parking spaces for Harriers also made with AM-2. Fuel bladders were emplaced, and other  infrastructure, including five expeditionary hangars was stood up. The derelict airstrip was transformed in a large expeditionary forward base for well over 60 Harriers, plus helicopters.

The Harriers could flow from the strip to deliver CAS against an iraqi attack in literally minutes.

Other forward sites and re-arming points were established. The Seabees took possession of another derelict landing strip at Tanajib, just 35 miles from the Iraqi border, and used AM-2 matting to expand the facilities and prepare a turnaround point for the Harriers. The strip used to be employed by helicopters.

The use of facilities built completely anew or adapted from beat up strips inadequate for other aircraft types enabled quick generation of a great number of CAS sorties, without clogging up the precious airbases needed by conventional aircraft. The use of forward refueling and rearming points kept the Harrier effective without needing to resort to air refuelling, which was already high in demand.


Again in Iraq, and in Afghanistan. In Enduring Freedom, most of the USMC Harrier fought from onboard ships. 60 of the 76 Harriers employed where seabased, coming in particular from USS Bataan and USS Bonhomme Richard, with both amphibious vessels operating as Harrier carriers. The other AV-8Bs operated from USS Nassau and USS Tarawa, with the balance flying from Kuwait. Forward basing capability was however nonetheless exploited, as many AV-8s made some use of a forward arming and refueling point (FARP) established by advancing ground forces at An Numaniyah, 60 miles south of Baghdad. The Harriers going into the FARP were the first coalition aircraft touching iraqi soil. The use of the FARP was precious particularly because it eased the strain on the ever-request air tankers.

In Afghanistan, the main contribution of Harriers to the opening phases of the war in 2001 were delivered by three LHD groups of six AV-8s each. Italian Harriers from the aircraft carrier Garibaldi also participated.

The STOVL nature of the Harrier proved invaluable for the british contingent when air support was brought forward. The Harrier GR7 (then GR9) was the only combat aircraft that could operate from the badly damaged airfield of Kandahar until the runway was extended and fully refurbished.
Extending the runway and getting it in suitable shape to accommodate the needs of the Tornado GR4 took time. In 2009, after five years in theatre, the Harrier force had to hastily add one last four-month squadron deployment while the extension to the runway was finally completed. From October 2004 to the end of its presence in Afghanistan, the british Harriers flew more than 22.000 hours in over 8500 sorties, expending almost 5000 CVR-7 rockets, 94 Enhanced Paveway II+s,  179 Enhanced Paveway IIs, 25 Paveway II and several Paveway IVs.

USMC Harriers have exploited their capability in other ways. The most impressive Afghan example is the building of the Camp Dwyer expeditionary airfield, built anew in the Garmsir District, Helmand river valley, just 20 miles away from Marjah, in preparation for major ground operations that the Harrier was then able to support closely. The expeditionary airfield started out as a FOB for Harrier, but over time had its AM-2 runway extended, and the whole base became a permament camp. The base has become so important that it s the last battalion-level base of the USMC in Southern Helmand during the drawdown of forces. This outpost has been critical in dominating one of the most dangerous areas of the whole Afghanistan. The camp is named in memory of British Lance Bombardier James Dwyer, 29 Commando Royal Artillery. It had been known earlier simply as FOB Garmsir.  



After decades of regular, intensive use in support of STOVL operations with the Harrier (as well as for bomb damage repair, expansion of various airfield surfaces etcetera) it is impossible to think that serious defence reporters ignore the nature and use of matting material, be it american AM-2 or british MEXE or anything in between.
The use of VTOL pads on operations and even for training is nothing new, and is not something that the F-35B brought along. Matting and Harrier have been comrades for years. The expeditionary, forward base operations have always included the use of pads and matting.

The US Marines actually maintain pre-positioned stocks of AM-2 matting and other equipment for the construction, from pretty much nothing but flat ground, of Expeditionary Airfields that in their complete form can include a 3850 ft runway with portable arresting gear set, parallel taxiway and parking space for 75 tactical combat aircraft and 3 C-130. The full-set EAF 2000 can allow even carrier borne combat aircraft to operate ashore, thanks to the arrestor wires. But such an installation, however, requires over 240 TEU containers worth of material that has to disembark, reach the intended area and be assembled there.

A full USMC expeditionary airfield set takes up the equivalent of more than 240 containers, but if you use every piece you get an airfield for 75 STOVL or carrierborne combat aircraft, from what was just a flat terrain. Preparing an austere base for STOVL aircraft only requires just a fraction of the equipment, time and logistic weight.

One such load is to be found on the ships of each squadron of the Marine Prepositioning Force.

The Forward Basing advantage of the STOVL component of USMC airpower is that it can use a base generated using a fraction of that equipment, as the british Harriers proved with the barebone strip at San Carlos. The F-35B will be able to take off with a short run, carrying much greater weapon load and far better sensors, and land on the forward base with a short vertical rolling landing. Or it will land vertically on an AM-2 pad. Yes, a pad will be required. Then again, it has always been so with the Harrier, as well.
It is true that AM-2 takes time to be installed (then again, teams of just an handful of men and a couple of forklift alone can actually put down an amazing amount of panels in a few hours) and has a considerable logistic footprint. But this has been known for years, and can hardly be solved from the aircraft side of the equation. The USMC is looking at what will come after AM-2, the AM-X, which will have greater heat resistance, will be more durable and, who knows, perhaps will come in more rapidly deployed packages.
There have been studies already in the past that evaluated, for example, the opportunity of developing a trackway-like solution for the creation of runways; something that can be rolled up and then distended quickly onto the ground like a carpet. 


Bill Sweetman, probably realizing that the story about the F-35B not landing vertically at RIAT had actually zero impact on operational capabilities, sneaked in a much more serious accusation: that the F-35B would also not be capable to make short rolling landings. Unfortunately for him, the F-35B already routinely makes vertical rolling landings on land, on AM-2 matting and on concrete runways, and has already displayed them at air shows as well. Sweetman could have watched them happen with just a quick search on YouTube. In this video alone, you can see two rolling vertical landings, one ending in a bolter with the aircraft taking off again (minute 4:30 onwards), the other with the F-35B getting to a full stop (minute 6:30 onwards). And more can be found in other videos.


And he is almost certainly going to see short rolling landings displayed at the air shows in the UK in July as well. The british government has also made clear in parliamentary written answers that the F-35B will routinely land vertically only on three purposefully built landing pads at RAF Marham, but will be able to make short landings on all other runways in the UK.

The landing pads to be built in Marham are hardly a surprise. Harrier bases have always had their own pads for the practice of vertical landings: Gutersloh had two pads, Wittering had MEXE pads, Cottersmore also had them, and USMC bases have purposefully built concrete pads.
It was always to be expected that pads would be built for the F-35B as well. The use of high-performance concrete, resistant to the heat, will make them safe and durable, allowing training to go on regularly.

British Harrier making a vertical landing on a MEXE pad at Wittering

So, is there a Vertical problem?  No, not really.
No one should actually be scared by this new and particularly weak attempt to deliberately attack the F-35B.

Personally, my F-35 worries are all on software development, reliability and maintainability, on properly fixing the weaknesses of the airframe's bulkheads to achieve the desired service life, and on integrating weaponry, including british specific weapons, as quickly and efficiently as possible. These are the important areas, and those where there are still too many question marks that i want to see solved one by one.
The rest is useless noise thrown up by people who have decided that they want this program dead, in a way or another, regardless of actual facts.




I've not gone into the details in this report, only tracing a history of expeditionary Harrier ops, to show how they have worked, and how they will work with the F-35B. For more details and images of the San Carlos FOB, you should visit this 2012 article by Think Defence.

Invaluable document on the story of the Harrier in RAF service, contained much of the information employed in this article: download