Is Army best served by Watchkeeper and Herti UAVs?

Discussion in 'Current Affairs, News and Analysis' started by tekirdag, Aug 4, 2009.

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  1. .

    Are Watchkeeper and Heriti the best UAVs the Army can purchase?

    Herti is a hugely overweight Fregati glider, and you cannot double the design-weight of an airframe without serious control problems (a 747 taking off at 800 odd tonnes??). The Herti weighs some 750 kg with a max payload of 150kg, but does not give an endurance (the most vital statistic). However, based on the engine and weights given, we can assume 19hrs.

    The Watchkeeper looks like a cruise missile with plank wings and shopping-trolly undercarriage, with all the problems that entails. Again, info is sparse, but working from the weights and the engine being used, endurance is likely to be 15hrs. The quoted 30hrs in Flight International is spurious, because the numbers just don't add up. (Unless this is a zero payload figure).

    But is this the best we can do?

    The Gem7, which was demonstrated at Aberporth this year, can out perform these UAVs in all respects. Based on a lightweight single-seat glider, it is:

    At 275 kg, nearly a third of the weight of Herti.
    A max 100kg payload is quite impressive.
    A max endurance of 48 hours is unbeatable (at 50kg payload).

    In addition:
    The Gem7 airframe has a glide ratio of 32:1, twice as good as the Herti and Watchkeeper, which is why it is so efficient (long endurance). You only need to look at Watchkeeper, with its long fuselage and pyloned plank wing, to know it will not fly efficiently.

    The Gem7 payload sits on the CofG, so mission changes are simple. Try that with Watchkeeper, and the thing will either end up on its nose or tail.

    The airframe can be dismantled and packed away in a trailer by two people inside 5 minutes. Can either of the others do that?

    At 275 kilos, the Gem7 is fully air-transportable into theatre.

    Approach speeds are far lower, for easy take-offs and landings.

    The baloon tyre can ensure operations from any farmer's field, something that the tricycle-wheeled Herti and Watchkeeper would find very difficult (especially with shopping-trolly wheels).

    The T tail allows for landing in crops.

    The airframe is supposedly less than a quarter the price of a Watchkeeper or Herti.

    Can the Army not do better than the choice they have made? Or are they going to end up with another very expensive Phoenix?
    (This critique of the Phoenix is worth reading, simply for the hilarity of it.)


  2. meridian

    meridian LE Good Egg (charities)

    I thought Herti was one of a long series of proof of concepts designed to inform future designs
  3. Herti has not been bought by the Army!
  4. What payload/payloads will the GEM-7 carry?

    "The Gem7 payload sits on the CofG, so mission changes are simple. Try that with Watchkeeper, and the thing will either end up on its nose or tail". Can the GEM-7 switch from EO/IR to SAR/GMTI in flight?

    Despite it's failings Phoenix was still one of the GOC's 3 main battle winners on Telic 1

  5. There's the rub as far as I'm concerned, I don't know how they manage to spend so much on things that don't have to be atall complex or at the cutting edge of technology. I mean, the ones that carry missiles and stay aloft for weeks, fair cop, but I would rather have alot of eyes in the sky that only stay there for a a day than one that can stay up for great lengths of time.

    But then again, any money saved would have to spent bringing defense astates houses up to habitatble standards or giving the TA enough man training days to actually train with. The money is much better wasted on over-spec UAVs.
  7. No, but Watchkeeper has, and it is even worse than the Herti.

    The quoted price is some £15 million a piece, or half the price of a Boeing 737-800. Que? £15 million??

    I think I saw a quoted price on the Gem7 of £1m a piece, so we come back to the argument of trimming the military budget to suit our new impoverished pocket. The Gem is British too, I understand.

  8. Yup, what he said, HERTI is a technology demonstrator that BAE are using to develop their UAS product line. The airframe is based on a motor glider as that's a fairly cheap place to start. They have a track record of flying prototypes (think EAP for Typhoon for instance) and with this being the prototype I don't think it's meant to be a serious contender for sales. They will no doubt sell you one if you ask though - it's called Fury if you want one that carries weapons.

    As to endurance, it's a fairly meaningless figure out of context. One UAV I worked with had a fuel flow of around a tenth of max in a holding pattern in still air at altitude; but if your UAV is tasked with a SAR racetrack it may well be at max for most of the flight. Transit from A to B generally burns more fuel than stooging around in the overhead. So the actual endurance depends heavily on what you're doing, what the winds are doing and so on.

    Now, as for Watchkeeper .. it's the wrong airframe for half of what it is meant to do. WK450 was designed to be a cheap and cheerful tactical UAV hence the use of constant cross-section structural elements (ie a tube is cheaper than a more aerodynamic shape). Give it an optical turret and you get decent real world persistence from sensible fuel loads. Plus it's relatively cheap.

    However .... slap a SAR on as well and it starts to creak a bit at the edges. Add to that the inevitable increase in fuel burn on a racetrack and all of a sudden it looks too small for the job.

    Were I in charge I'd have bought two airframes - one smallish for tactical EO, one larger for SAR, comms relay, SIGINT and so on (probably twin boom, more real estate for antennas). That's not to say you can't overload Watchkeeper and do those jobs, you can, but fuel burn will go up and endurance down.

    Bear in mind that if you do it right - ie copy the Israelis - everything but the airframes are common. It is nowhere near as difficult as operating two manned platforms, for instance.

    Oh, and landing on fields is a bit of a red herring. Modern UAVs almost exclusively autoland as that way far fewer get bent (just ask the USAF about their Predator/Reaper loss rates relative to the US Army and Warrior). That means you need a pre-surveyed area with installed equipment so you might as well stick in a PSP strip and a cable as well. Or use a road, an airfield etc. Otherwise you need an extremely skilled external pilot with very perishable skills - the Israelis talent spot from model aircraft flying clubs for theirs.

  9. Payload varies from 50kg to 100kg, depending on the endurance required.
    Any payload can be carried, depending on the mission, that's up to the user. If BP or Shell want mineral surveying, that's possible too. Plug in the kit, and off it goes.

    I'm still trying to find a website.

  10. The Watchkeeper programe was supposed to consist of two levels of UAV a tactical based on the 180 and strategic based on the 450. The 180 was dropped to save money as was that part of the programe where the army would get the 450 on loan as an interim measure between Phoenix and Watchkeeper.

    It is also worth remembering that the project was initialised some years ago, well before many of the lessons learn't in Telic and Herrick.

    Needless to say when the system enters service and replaces the H-450 there will be no reduction incapability and in many ways an enhancement in capability.
  11. Yes, but you have to get an idea of endurance somewhere. To calculate for Gem7, Herti and Watchkeeper, I used a 60% loiter power setting for the quoted engines.

    And all the extra expense, personnel and weight of equipment. Are there that many paved roads to use in Afghanistan? Since the Gem7 lands easily on fields, an autoland via GPS onto a known flat patch of land is simplicity itself. The autopilot comes with autoland as standard.

    The point is that the Watchkeeper undercarriage will not allow rough field landings. Tricycle and rough strips do not mix, while small trolly-wheels are just asking for trouble.
  12. tekirdag,

    I would heartily recommend against taking anything Lewis Page writes at face value. He's an extremely poorly informed and partial so called 'military expert'.

    That said, WK could have been done better by the Army. The biggest issue is that it should be operated by the AAC rather than the RA.

    I also enjoy comparing the cost effectiveness of UAS such as WK with those of light turbo prop assets such as the Cessna Grand Caravan and King Air. UAS certainly have their place, but are not a panacea.

  13. The point is that the Watchkeeper undercarriage will not allow rough field landings. Tricycle and rough strips do not mix, while small trolly-wheels are just asking for trouble.

    Actually you are very wrong as recent Watchkeeper trials have shown
  14. I think the Gem7 proposal was originally made in 1994. Ignored by the powers that be, one presumes.


  15. So why all that huge expense of extending the runway at Aberporth, if a grass strip is adequate? Having flown Cessnas and Piper Cubs from rough old farmer's strips, I know which I would prefer.

    P.S. The reason for preferring a farmer's field, is that you don't have to worry about cross-wind take-off and landings, which could severely curtail opps from a road or paved runway. "Sorry, no surveilance today, its too windy".