1. The
Saint Bernard Emergency Airborne Supply Drop (EASD) Vertical Take-off and
Landing (VTOL) Unmanned Aircraft System (UAS).
1.1 For this exercise, hypothetical
manufacturer We Fly Fast Dones, Inc. (WFFD) is developing an electric powered VTOL
named the Saint Bernard for its’ ability to bring emergency supplies to those
in need. The Saint Bernard UAS is to be
used as a method to deliver sub 20-pound loads of emergency supplies during
civil disasters to stranded personnel awaiting rescue such as in an urban flood
setting. The Saint Bernard is to be a
GPS tracked, electric powered, human-portable VTOL with an air vehicle weight
inclusive of payload of no greater than 55 pounds, flight time under full load
of 60 minutes, a maximum working altitude of 400 feet above ground level (AGL),
navigated via first person view (FPV) camera system, and controlled via a
commercially available of the shelf (COTS) transmitter system. Base requirements reviewed in this document
are cost, payload, and air vehicle.
1.2 Manufacturer’s costs
are generally difficult to obtain, consequently costs for the hypothetical
system are loosely based on retail prices of various commercial off the shelf
(COTS) hardware. Payload requirement was
determined using the estimated weight of an emergency supply kit consisting of
water packs, an emergency radio, first aid kit, food rations, and miscellaneous
survival items. The Deluxe Personal
Safety Emergency Pack 4 Person 3 Day Emergency Preparedness Kit available from
the American Red Cross was used as a representative payload (American Red
Cross, n.d.). Buoyancy requirements for
the emergency supply canister (ESC) were included in the eventuality that the
canister is inadvertently dropped in a flood situation. As saltwater is approximately 3% more buoyant
than freshwater (Seed, 2011.) there is no saltwater buoyancy requirement
stipulated. Air vehicle requirements are
based on the operational necessity of transporting a 20-pound load to a
specific location.
2. System
development
Months
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3
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6
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12
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15
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18
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21
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24
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28 +
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Phase
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1
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Concept design
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1
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2
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Concept research
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2
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3
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Preliminary design
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3
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4
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Detail design
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5
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5
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Specimen test
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7
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6
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Prototype build and test
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12
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13
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7
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Development
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14
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18
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8
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Certification
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18
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9
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Production
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19
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48
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10
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Support
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19
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120
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Figure 1 System
Development
2.1 System development
shall use a 10 phase Waterfall method (Austin, 2010) over a 120 month period
with all development completed by the end of the 18th month and
production beginning in the 19th month and ending in the 48th
month. Service and support will continue
through the 120th month. See
figure 1. Testing strategy consists of
component testing, integration testing, test site selection, test site
preparation, flight-testing, and certification (Austin, 2010). See figure 2.
Months
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3
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6
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9
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12
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15
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18
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Process
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Component testing
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5
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Integration testing
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6
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Flight test site
selection
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5
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Flight test preparation
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6
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Flight testing
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7
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18
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Certification
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18
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Figure 2 Testing Strategies
3. Baseline requirements
3.1. Cost:
The net cost of the UAS including hardware, associated software, emergency
supply canister (ESC), and support equipment, is to be no more than $24,150.0
3.2. Payload: The air vehicle shall have a payload capacity
of 20 pounds in a user removable, weather resistant, emergency supply canister
(ESC) comprised of a commercially available Pelican model iM2750 Transport case
(Pelican, n.d.).
3.3 Air
vehicle: The air vehicle shall be
capable of achieving all designed flight operating characteristics with a 20
pound test weight in the ESC with the exception of maximum speed which is
achieved without a service load.
4 Derived requirements
4.1 Cost
4.1.1 Air vehicle
including one installed battery pack, GPS unit and associated GPS software
shall not exceed $20,000 net cost.
4.1.2 FPV camera
system shall not exceed $1000.00 net cost.
4.1.3 FPV monitor
shall not exceed $250.00 net cost
4.1.4 ESC shall not
exceed $400.00 net cost.
4.1.5 Transport case
shall not exceed $1500.00 net cost.
4.1.6 Radio control
system shall not exceed $1000.00 net cost.
4.2 Payload
4.2.1 ESC shall be
removable from the UAS without tools.
4.2.2 ESC shall be
removable from the UAS without verbal instructions.
4.2.3 ESC shall be
able to be reinstalled on the UAS without tools.
4.2.4 ESC shall be
able to be reinstalled on the UAS without verbal instructions.
4.2.5 ESC shall be
capable of surviving direct contact with freshwater to a depth of 3 feet for 15
minutes with no evidence of water intrusion.
4.2.6 ESC shall be
capable of surviving direct contact with saltwater to a depth of 3 feet for 15
minutes with no evidence of water intrusion.
4.2.7 ESC shall be
capable of floating independently in freshwater with an internal 20-pound load
for a period of 15 minutes without evidence of water intrusion.
4.3 Air vehicle
4.3.1 Maximum flight radius of 2.0 miles.
4.3.2 Endurance in
calm wind of 60 minutes.
4.3.3 Typical
operating altitude of 150 feet.
4.3.4 Service altitude
of 400 feet AGL.
4.3.5 Cruise speed
of 45 miles per hour.
4.3.6 Able to hover
at 150 AGL.
4.3.7 Vertical climb
rate of 50 feet per second.
4.3.8 Cross wind
stability of 25 miles per hour.
4.3.9 Maximum speed 60 miles per hour no load.
5 Testing requirements
5.1 Cost
5.1.1 Air vehicle
5.1.1.1 Using industry accepted accounting methods verify
that the combined total net manufacturing cost, exclusive of overhead, of the
air vehicle calculated by multiplying the hours spent in construction of one
standard vehicle by the current corporate labor rate plus the net cost of
associated components including one installed battery pack, GPS unit and
associated GPS software exceed $14000.00.
5.1.2 FPV
5.1.2.1 Verify through
review of purchase agreements and invoices that the WFFD purchase cost, inclusive
of shipping to WFFD’s manufacturing facility, as negotiated with the supplier
of the COTS FPV does not exceed $1000.00.
5.1.3 FPV monitor
5.1.3.1 Verify through
review of purchase agreements and invoices that the WFFD purchase cost,
inclusive of shipping to the WFFD manufacturing facility, of the COTS FPV
monitor as negotiated with the supplier does not exceed $250.00.
5.1.4 ESC
5.1.4.1 Verify through
review of purchase agreements and invoices that the WFFD purchase cost,
inclusive of shipping to the WFFD manufacturing facility, of the COTS ESC as
negotiated with the supplier does not exceed $400.00?
5.1.5 Transport case
5.1.5.1 Verify through review of purchase agreements and
invoices that the WFFD purchase cost, inclusive of shipping to the WFFD
manufacturing facility, of the COTS transport case as negotiated with the
supplier does not exceed $1500.00?
5.1.6 Radio control system
5.1.6.1 Verify through
review of purchase agreements and invoices that the WFFD purchase cost,
inclusive of shipping to the WFFD manufacturing facility, of the COTS radio
control system as negotiated with the supplier does not exceed $1000.00?
5.2 Payload
5.2.1 Removability
5.2.1.1 Remove the ESC from the airframe without tools.
5.2.1.2 Remove the ESC
from the airframe without physical assistance or verbal directions.
5.2.3 Attachment
5.2.3.1 Attach the ESC
to the airframe without tools.
5.2.3.2 Attach the ESC
to the airframe without physical assistance or verbal directions.
5.2.4 Submersion survival
5.2.4.1 Place a
moisture indicator strip in the ESC, close case according to manufacturers’
directions and submerge in a freshwater tank to a depth of 3 feet measured at
the bottom of the case with the case in an upright position for a period of 15
minutes.
5.2.4.2 Retrieve case
from freshwater tank and through visual inspection of internals and condition
of moisture test strips verify that no water infiltration has occurred.
5.2.4.3 Place a
moisture indicator strip in the ESC, close case according to manufacturers’
directions, and submerge in a saltwater tank to a depth of 3 feet measured at
the bottom of the case for a period of 15 minutes.
5.2.4.4 Retrieve case
from saltwater tank and through visual inspection of internals and condition of
moisture test strips verify that no water infiltration has occurred.
5.2.5 Buoyancy
5.2.5.1 Place a
moisture indicator strip in the ESC, close case according to manufacturers’
directions, and place in a freshwater tank for a period of 15 minutes.
5.2.5.2 Observe case for 15 minutes and verify that the top
of the case does not submerge below the uppermost hinges.
5.2.5.3 Retrieve from
test tank, open case and through visual inspection of internals and condition
of moisture test strips verify that no water infiltration has occurred.
5.3 Air vehicle
5.3.6 Flight radius
5.3.6.1 With a 20 pound
test weight in the ESC and a fully charged battery pack, bring the UAS to the
service altitude of 400 feet, fly out at cruising speed to a point 2 miles from
the launch pad and fly in a 360 degree circle around the launch area at a
radius of 2 miles and upon completing the circle return to the launch pad.
5.3.7 Endurance
5.3.7.1 With a 20 pound
test weight in the ESC and a fully charged battery pack, bring the UAS to the
service altitude of 400 feet, fly out at cruising speed to a point 2 miles from
the launch pad and fly in a 360 degree circle around the launch area at a
radius of 2 miles continuing for a total elapsed time of 60 minutes before
returning to the launch pad.
5.3.8 Operating altitude
5.3.8.1 With a 20 pound
test weight in the ESC and a fully charged battery pack, bring the UAS to the
service altitude of 150 feet, fly out at cruising speed to a point 2 miles from
the launch pad and fly in a 360 degree circle around the launch area at a
radius of 2 miles continuing for a total elapsed time of 60 minutes before
returning to the launch pad.
5.3.9 Service altitude
5.3.9.1 With a 20 pound
test weight in the ESC and a fully charged battery pack, bring the UAS to the
service altitude of 400 feet, fly out at cruising speed to a point 2 miles from
the launch pad and fly in a 360 degree circle around the launch area at a
radius of 2 miles continuing for a total elapsed time of 60 minutes before
returning to the launch pad.
5.3.10 Cruise speed
5.3.10.1 With a 20 pound test weight in the ESC and a fully
charged battery pack, bring the UAS to the service altitude of 150 feet, fly
out at cruising speed to a point 2 miles from the launch pad and fly in a 360
degree circle around the launch area at a radius of 2 miles continuing for a
total elapsed time of 60 minutes before returning to the launch pad.
5.3.11 Hover
5.3.11.1With a 20 pound test weight in the ESC and a fully
charged battery pack, bring the UAS to a hover at 150 feet AGL and remain in
hover for a period of 15 minutes then return to launch pad.
5.3.12 Climb rate
5.3.12.1 With a 20 pound test weight in the ESC and a fully
charged battery pack, bring the UAS to a hover at 10 feet AGL then climb
vertically to a maximum altitude of 400 feet AGL; time the ascent with a
chronometer.
5.3.13. Crosswind operability
5.3.13.1 With a 20 pound test weight in the ESC and a fully
charged battery pack, bring the UAS to a hover at 10 feet AGL, then using
(hurricane) fans producing a cross wind velocity of 25 miles per hour over an
area approximately 15 wide fly through the crosswind ensuring UAS maintains a
straight course.
5.3.14 Maximum speed
5.3.14.1 With no test weight in the ESC and a fully charged
battery pack, bring the UAS to the service altitude of 150 feet, fly out at
cruising speed to a point 2 miles from the launch pad perform a 180 degree turn
towards the launch pad and while maintaining cruise altitude accelerate to
maximum speed in a straight line; upon reaching the launch pad reduce speed to
hover and land the UAS.
References
American Red Cross.
(n.d.). American Red Cross Store.
Retrieved from
http://www.redcrossstore.org/item/20-04667
Austin,
R. (2010). Unmanned aircraft systems UAVs design, development and
deployment. Chichester: Wiley.
Pelican.
(n.d.) Pelican Storm iM2750 Case
– Yellow. Retrieved from
Seed. (2011). What
is the buoyancy difference between fresh water and salt water?
SEED. Retrieved from http://www.planetseed.com/faq/water/what-buoyancy- difference-between-fresh-water-and-salt-water.
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