December 2007

Introduction

From the AlphaSim Reference Notes: The Grumman EA-6B is a modification of the basic A-6 airframe into a long-range, all-weather, advanced electronic countermeasures platform. It is the U.S. Navy and Marine Corps primary electronic warfare platform and has seen action in nearly every conflict since its introduction in 1971. A total of 170 examples were produced and the aircraft is still in active service.

In my Navy days, I saw many of the predecessors of this aircraft, the basic Grumman A-6 Intruder. Seeing this airframe brings back some memories for me of a time when I had no grey in my hair and more fire in my belly. The Intruder has morphed into something else entirely too, the Prowler. The Intruders are gone, retired from active service in the late 90s. The Prowlers remain.

They were a marvel when introduced. I recall that aviation technology at that time, even as practiced by the military, was considerably more primitive that what we now enjoy. There was no GPS system.  Microprocessors were just beginning to come into use. Glass cockpits, Cat III approaches, autoland, RNAV, FMCs, TCAS and a whole host of high-tech tools the modern pilot might have at his disposal were just a gleam in the eye of far-seeing designers. It is easy to lose sight of the fact that these now-dated aircraft, both the Prowler and its older, slightly smaller but very similar looking brother, were very high-tech for their time. They both brought new capabilities, largely contained within high-tech black boxes, to the combat flight environment. That made both aircraft truly revolutionary in their individual roles. Each could do things none of their predecessors could.

The Prowler was developed from the Intruder airframe to meet a requirement that was born of an ongoing war in Vietnam. An urgent need was recognized for a dedicated electronic warfare platform able to operate from the carriers. The aircraft that fulfilled that requirement would need performance comparable to that of the other aircraft for whom it would run electronic interference, the Intruders, Skyhawks (…think A-4, not C-172), Phantoms, Corsair IIs and Crusaders. It needed the same all-weather capability. It also needed the ability to cloak its companions from the all-seeing eye of the Russian and Chinese air defence systems that were pervasive.

Using the basic A-6 Intruder airframe, already in production and proven, Grumman changed it remarkably little. The strong airframe, great load-carrying capability and high performance that the Intruder already possessed were employed to great advantage to make its spun-off cousin as good at its job as the Intruder was in the attack role.
 

Down to business

The Prowler, the EA-6B is the bird Grumman produced and that’s the bird AlphaSim has provided us with in this excellent add-on. AlphaSim has done a commendable job with it.

The external model is excellent. Four model variations are provided, all the same basic airframe but with different under-wing stores attached and different paint jobs, two Marine and four Navy. Navy and Marine Corps squadron paint schemes can be quite colourful and these six don’t disappoint. They are interesting and appear to be accurately done. Under-wing and centre-point stores consist of various mixes of AN/ALQ-99 jamming pods, fuel tanks and AGM-88 HARM missiles.  You’re going to love the eye candy.
 

4 models / 6 paint schemes

The aircraft is available by download only as is standard with all AlphaSim products. Installation was quick and easy with no surprises or difficult spots.

Now lets jump into the cockpit with three of our closest friends and fly it. Cockpit visibility is very good, both on the ground and in the air. There’s a nice touch with canopy reflections; they don’t interfere with the view, but if you pan or view something that’s moving relative to the aircraft, it’s very obvious that there’s a layer of transparent material between you and the outside world. It’s a very subtly done effect that you don’t notice until there is motion; it’s incredibly realistic. There are also reflections on some of the instrument faces. Most notably, if you go to the VC and pan down to the radar scope near the bottom of the panel, there’s a large reflection of a handsome devil in helmet and oxygen mask staring back at you.
 

Handsome Devil!

The panels are nicely done in both the 2D and 3D mode. There are roll-over Tool Tip tags available on most of the instruments and controls, though not all. Four standard FS pop-up buttons bring up the native FS ATC, Map, GPS and Kneeboard. There are three additional non-FS style buttons on the panel that bring up radios, autopilot and some engine and electrical functions. There are two very good files included that come up on the Kneeboard’s Reference and Checklist pages, much better than are normally seen. Of course the standard ATC, Flight Plan and FS Key Assignment pages are also on the Kneeboard. In the FSX version the radar in the 2D panel is usable in a popup.

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2D Panel	Sub-Panels

The panel includes a radar altimeter, but I could find no way to set the DH alert. Of course the obligatory AoA Indexer (Angle of Attack) is present on the left canopy frame, as it is on any carrier-capable USN aircraft. Integrated with the AoA display are a pair of very handy illuminated switches for the speed-brakes and tail-hook as well as a big, red landing gear warning light. It would be hard to miss that one. Nearby, on the top-left edge of the panel is an AoA gauge. This little corner of the world becomes an area of intense focus for intrepid Naval Aviators when motoring down the glide slope to the boat.

The vertically oriented tape style engine instruments are present in three pairs on the lower left of the panel but are poorly labeled in both views and these particular instruments have no Tool Tips to help out. The 3D panel provides four additional engine gauges below the tapes. There is no fuel quantity instrument visible in the 2D panel, though one is available on the 3D view. There is a very nice red LED dual DME readout and NAV radio control that displays the frequency and the three-letter identifier of the station tuned. It remains visible when the radio stack is hidden. It can be switched between NAVI and NAV2 and also displays the DME readout for both NAV sets simultaneously. It’s the best thing of its type that I’ve ever encountered. If this is typical, I’m going to have to fly jets more often.
 

The centre console sports a number of switches, buttons, knobs and the like. A number of them operate, many do not. Of those that operate, most have Tool Tip labels; some do not. The function of the latter are a mystery and they may well have no function at all – just ambiance. The left hand side console also has an array of switches but none respond to the mouse. There are working power levers and a flap lever on that side – nothing else there is functional. The cockpit looks good. Panning around in 3D view you really get the feel you’re in the aircraft. It looks like it ought to. One possible deficiency is the lack of any portion of the left wing visible in the 45 degree left rear view. It looks like part of the wing ought to be visible in that view, but it’s not. It’s a small point.

DME Gauge

A nice feature included on the kneeboard reference list is a table of weights for the various under-wing stores. The aircraft has dedicated loading stations for each of the four crew (you can simulate your mother-in-law in the right rear by setting it to 400 lbs), 200 lbs of survival gear, drop tanks and various hard-points for HARM missiles and jamming pods, five in all. There is nothing to prevent you configuring the aircraft weight accurately for any of the provided combinations of under-wing hardware and all the information needed to do so is on the kneeboard, a nice touch.

Ground handling is easy and precise. Unlike some AC, full rudder without differential braking results in a reasonably short radius turn, no doubt just the thing on a crowded carrier deck. The throttle lag typical of turbojets is quite pronounced and feels realistic. Taxiing at a smooth, constant speed is a bit like driving on ice in that you must have an “anticipation horizon” a little further out ahead than you may be accustomed to if you normally fly piston engines.

Engine and cockpit sounds are quite good, the engine sounds particularly so at higher power settings. Cockpit noise persists after a total shutdown, even after opening the avionics and battery switches. One assumes it must be a ground power unit operating nearby.

Unexpectedly, this aircraft is a hot rod! Well, yes, it’s sub-sonic, the engines are non-afterburning and it’s a 50,000 lb plus AC with a thrust to weight ratio less than 1, but it’s not an under-powered slouch. It’s powerful, fast and slippery. To me it flies like a heavy biz-jet – on steroids. In my first long flight I climbed from near sea level to 15,000 feet at 230 knots with the VSI pegged at 6,000 + ft/min. the whole short time. That’s as high as I was going, but I didn’t have any sense that I was running out of steam. Keeping the Prowler below the 250 KIAS ATC speed limit in level flight below 10,000 feet takes some concentration. The throttles have to come far back to avoid speed excursions above the 250 knot limit.

Handling in the air is crisp and responsive. The roll rate is excellent (see description below of the ailerons). Lateral stability is quite good. Longitudinal stability is another matter. Pitch requires careful attention…or the autopilot. Maintaining an altitude manually is possible, but requires painstaking concentration. I suspect it is so in the real AC as well.

Takeoff is a rush. The Prowler accelerates quite well, particularly if you hold it with the brakes until the engines spool up. It requires a relatively high speed to lift off. Rotation at 130 knots is standard and I have not seen the AC lift off below about 140 knots. This requires a fair amount of runway if heavy, but once the wheels are in the wells and the flaps up, performance is very, very good for an aircraft in this weight class. Care is needed to see that the pitch trim is set neutral for takeoff. There’s a gauge, but it’s only in the VC cockpit and only viewable by moving the stick to one side. I had to look for a long time before finding it. Check it before you start rolling, you won’t be able to manage it on the fly.

A moderately effective speed brake is provided, consisting of a pair of short spoilers on the trailing edge of the wings at the tips. They deploy by splitting, one half deflecting upward and the other downward, producing a front-on view that is uniquely Prowler/Intruder. Because they are split, the speed brakes don’t seem to cause any pitch change. Opening and closing them as needed is quick and simple and the only reaction from the AC is the one you want, speed. Of course if you leave them open and slow too much you’ll sink or will have to pitch up to remain level, but that’s just Wilbur and Orville 101.

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Distinctive Speed-Brake Configuration

The ailerons and flaps are...odd. They are really two parts of a single wing section, unlike the more normal configuration where the ailerons lie outboard of the flaps. The entire trailing edge is involved in AC control. At the outer tips are the speed-brake panels, but they are short, not extending far inward from the tips. Everything inboard of the speed-brakes to the wing root is both flap and aileron. The lower part, of course, is the flap. Above and just forward is a spoiler-like control surface that deflects upward for roll control – there is no corresponding downward deflection on the opposite side. Since the surface is so long, extending all the way from the root out to the short speed-brake section near the tip, it is quite effective. There are only two flap settings – I came to think of them as “almost all” and “all”. Leading edge slats deploy in conjunction with the flaps, a pretty neat effect in the external view. I assume the odd aileron configuration accurately reflects the real aircraft.
 

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Flaps, Slats, Speed-Brakes, Right Aileron	Sexy Exhaust Flames

In flight there are good contrail ribbon effects off the open speed brakes at the wing tips and a well-rendered, smoky jet exhaust effect. An external view shows fire in the exhausts at higher power settings, looking a lot like afterburner manifold-rings, but this AC doesn’t have afterburners. The effect is only visible within the exhaust nozzles – there’s no external tongue of flame or shock cone. I don’t think that effect is accurate, but to be honest I’m not sure. It is sexy though!

Tip Contrails and Condensation Effect Near Wing Roots

This is a very well done add-on. I find the external models very satisfying. The 2D and 3D cockpits are functional for either drilling holes in the sky or a serious IFR flight. The latter attribute is sometimes poorly implemented in add-on military AC, which the publishers seem to think are only ever flown in severe-clear ACM. My testing was all in FS9 and even with all the sliders all the way up, performance never faltered.

Animations include front and rear canopies and the associated folding steps, the tail-hook, wing fold, speed-brakes and of course the usual landing gear, flaps, slats and other flight control surfaces. There is a key for toggling the aircrew AWOL or all-present-and-accounted-for. All those animations are well done.
 

There is a reference page htm file and the checklist file along with a brief read-me that provides some much-needed information, but there is no manual provided and there’s more information needed. A 2D and 3D cockpit diagram and some explanation of how certain things (e.g. AoA indexer, DME gauge) function would be most welcome.

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It is worth mentioning here the full FSX version takes this aircraft into another dimension. The guys at AlphaSim certainly know how to make the best from the SP2 SDK, the FSX version gets the added bonus of bump mapping, self shadowing externals, VC Self shadowing (requires FSX, SP2 and Vista) a working radar popup in 2D mode and 2 rear cockpit views. (This final feature not modelled in the FS9 version).  If you don't have FSX It's worth upgrading just to get these features!

Rear VC view in the FSX model

In summary, this is a very well programmed package. The external model, flight model and performance is very, very good. It’s a lot of fun to fly!


John Allard
 

Links:: Alphasim home • Prowler product page • Support Forum US Navy Prowler fact file • Northrop Grumman