Bad Navy III

F-35 is obsolete and other fun facts.

  The navy is planning on building a remote control helicopter called the Firescout and base it on destroyers.  Back in the day of autogyros there was a joke; with an autogyro  you got half the speed for twice the horsepower.  A similar truth exists for helicopters, from basic rotor analysis the disc loading, weight divided by area of the rotor, times the magic number of 800 (actually 793, but whose counting) gives the speed of air downflow squared in feet per second.   That number must be increased by about 1/3 to allow for actual loses.  That speed times the weight divided by 550 ( lb-ft/sec, the number for horsepower) gives the horsepower required for static lift.  At cruising speed the horse power required is about 1/2 that.  So, for weight, W,
and disc loading of 5 lbs/square foot, square root of 5 X 800 = 63 X 1 1/3 = 84.  Hp = W X 84 / 550/ 2 =
0.076 or 7.6 % of weight.  A winged UAV has weight divided by lift to drag, times speed, in fps, divided by propellor efficiency, divided by 550.  A UAV can easily have 20:1 lift to drag at a speed of 400 fps, 270 mph.
Propellor efficiency could be 80%.  W/20 X 400 / 550 / .80 = 0.045 or 4.5%.  Fuel use is proportional to horsepower.  The UAV could have over 50% longer endurance and, allowing a speed of 200 fps, 130 mph, for the helo, over 3 times the range. The Firescout is stupid.  They only place it can be justified is over land where it can hide by flying low over ground cover.

   Rather than build a UAV as a helicopter, it is more efficient to launch a winged UAV with a helicopter.  Suspended underneath the helicopter, b, is a small robotic plane attached to a tether, c.  Underneath the plane are two jaws which close over a triangle which can be raised from the top of the UAV. The helicopter hovers over and attaches to the UAV which is placed on the helideck.  The helicopter rises and flies forward until the UAV has achieved flight speed of 120 mph or so.
   For recovery, the helicopter would approach from the back of the UAV.  This prevents the rotor downwash from destabilizing the UAV, the downwash moves relatively downward and backward from the helicopter.  The little plane on the cable would have an electric motor and propellor to enable it to maneuver freely.  It would be positioned over the triangle of the UAV after the triangle is raised.  It would then close its jaws to allow the helicopter to lift and land the UAV.
   The UAV would be stored with its wings and empennage folded, d, e.  On the deck the UAV would be placed on a cart for moving.  In the hangar one UAV would be lifted by its triangle and then brackets would be swung out from the wall for support, a second UAV would be left on a cart and stored underneath the first.  The hangar would have to be wider so vertical launch tubes for missiles located between the hangars would have to be moved and the ship would need a larger hull.
   The destroyer would be able to lauch reconnaisance and project force over 1 000 miles form its location.   It would be a good idea to add a laser tracker to cruise missiles sot the UAV could target them.  There would be a delay in awaiting the arrival of cruise missiles and the UAV could be provided with bombs or missiles for on board carriage.  The size of the UAV would depend upon the size of helicopter available.  The Seahawk, the naval version of a Blackhawk, should be able to lift at least a 6 000 lb UAV.
   Accompanying destroyers could provide reconnaissance for a carrier, freeing up carrier deck space.
   A ship larger than a destroyer could be built.  Instead of two hangars, like a destroyer, it could have three, instead of one bay in each hangar it could have four.  The rearmost bay would have 1 helicopter and 2 UAVs, the other 3 bays would have 2 UAVs on each wall and a movement corridor in between.  That would give 3 X 4
+ 2 = 14 UAVs in each hangar X 3 hangars = 42 UAVs total.
   Destroyers have about 100 vertical launch tubes, VLTs,  for Standard missiles ( anti-aircraft and anti-ship) and cruise missiles (ground attack).  The bigger ship could have 200 VLTs, 100 for Standard missiles and 100 for cruise missiles.  The ship would be a mini aircraft carrier.  10-15 would be kept at sea, in the event of a crisis, they would move towards it and begin launching UAVs for reconnaissance, the pilots would be linked to the UAVs through satellites and would be stationed at shore bases.  If a carrier battle group is dispatched the ship would provide most of the surveillance and reconnaissance for the carrier.  If a Marine landing groupi dispatched it would provide reconnaissance and secondary air strikes to assist them.  It would be equipped with low signature UAVs as well as Aegis radar and a 5 inch gun so it can self deploy without any additional escort.  It would weigh 15 000- 20 000 tons empty.
  A second ship could be built with 3 or 4 hangars and a speed of 20-25 kts.  It would be equipped with high endurance, propellor-driven, UAVs.  It would carry only light cannon for defense. It would be useful in locations such as Somalia and to support Marine landing groups if there is only limited air defense.  It would also weigh
15 000-20 000 tons but would have longer endurance and more fuel and supplies for the UAVs.
  The navy has shown concern for a swarm of small boats attacking naval vessels.  A UAV patrolling beyond the horizon would provide advanced warning of approach.  The UAV could also carry laser guided mortar shells, see post New Army, which it could drop from altitude on small boats, guiding them by laser to each target.  The operator for the UAV could be aboard ship and use line-of-sight radio to avoid satellite delays.  The mortar shells do not need to be guided continuously form being dropped, they could be dropped from 30 000 ft and guided by laser below 5 000 ft allowing shells to be dropped consecutively without awaiting the previous shells detonating.  This attack method could also be used against a column of ground vehicles to support marine landing forces.
   A UAV such as this, as well as a tethered copter, such as post Bad Navy II, could also be installed on Coast Guard high endurance cutters to increase their search and surveillance capabilities.
  This was another suggestion ignored by DARPA and the navy.