Engineering.purdue.edu



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AAE 451

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UAV PROPOSAL

SYSTEMS REQUIREMENTS REVIEW DOCUMENTATION

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TEAM 4

Kevin Kwan

Dan Pothala

Mohammad Abdul Rahim

Nicole Risley

Table of Contents

Table of Contents………………………………………………………………………………… 2

Executive Summary ……………………………………………………………………………… 3

1.0 Introduction…………………………………………………………………………………... 4

1.1 Product Definition……………………………………………………………………….. 4

2.0 Business Case…………………….………………………………………….…..……………. 5

2.1 Target Market……………..…………………………………………………………….. 5

2.2 Competition…………………………………………………………………………….....5

2.3 Market Size……………………………...............................…………………………… 10

3.0 Customer Attributes…………………………………...…………………………….………..16

3.1 External Customer Attributes.…………...………………………………….…………16

3.2 Internal Customer Attributes..……………………………………………….………...17

3.3 External Regulating Influences……………….……………...………………..……….17

3.4 Quality Function Deployment……...……........................................……………...……19

4.0 Concept of Operations………………………………….………………….…………...……. 23

4.1 Mission Analysis: Case 1 – Long Range Coverage……………………………………23

4.2 Mission Analysis: Case 2 – High Endurance Coverage………………………………25

4.3 Mission Analysis: Case 3 – Long Range Pursuit..………………………………..……27

5.0 Current Design Requirements………………………….………………….……………..…. 29

5.1 Payload.………………….……………………………………….……………………... 29

5.2 Constraint Analysis………………………...............................……………………........31

5.3 Sizing.………………….……………………………………….…………………...…... 34

5.4 Trade Study………………………...............................……………………...............….36

5.5 Project Timeline Description………………………………….……………………..... 39

6.0 Summary……………………………………………………………………………………... 41

7.0 References……………………………………………………………………………………..42

A.0 Appendix A…………………………………………………………………….…………….. 44

A.1 Aircraft Database …………………………………………………………………....... 44

EXECUTIVE SUMMARY:

Throughout the world today, there is an increased demand for Unmanned Aerial System (UAS) in many different industries for many different purposes. A particularly high need has developed for UAVs with continuous area coverage capabilities. There are several industries in which these vehicles would be useful; however, few options are available for the customer at an affordable price. In recent years, there has been a realization among aircraft manufacturers and the public in general of the huge potential that exists in a civilian UAS market. Law enforcement and news agencies, with their helicopter fleets, have to deal with acquisition costs in the millions, and operating costs in the thousands of dollars every hour. The market is ready for the introduction of an Unmanned Aerial System that can provide most of the advantages of a helicopter, while providing huge cost savings and eliminating the risks of putting a crew in the air.

1. Introduction

1. Product Definition

The Metro-Scout UAV will be a remotely flown, multi-purpose Unmanned Aerial System designed to operate over highly populated metropolitan environments safely and quietly, in support of the activities of various news agencies and law enforcement departments nationwide. It will be designed to do continuous area coverage and meet all current FAA regulations for an Unmanned Aerial System operating in airspace over urban areas in the United States. News and law enforcement agencies have distinctly different missions that would require different payloads, which is why multiple payload options for the same airframe will be addressed.

2. BUSINESS CASE

2.1 Target Market

Team 4’s business strategy is targeted primarily at providing a cost-effective UAS alternative to News Agencies and Law Enforcement Agencies. These Agencies have traditionally relied on helicopters for their operations, and incur large expenses in acquisition and operating costs.

The emerging UAV market presents many avenues for profit; however, the smaller size of UAVs means that a potential player in the field need not have all of the resources of larger-scale operations, such as Boeing, Lockheed-Martin, or Airbus. This translates into a larger, more competitive pool with which to vie for contracts and sales. Turning a profit in this type of arena will hinge on selling technology at the most competitive price possible while proving it will provide service beyond requirements in a reliable manner. Improving current technologies, creating a versatile vehicle, and evaluating the market to determine possibilities for maximum sales will allow Team 4 to profit from the Metro-Scout UAV design.

Generating profit requires creating a demand for Team 4’s UAS product, which starts with designing the UAS to be more advanced and to perform better than current UAS models in its realm of operation. Careful and efficient design is necessary here to keep costs at a minimum, as the use of new technology can result in less-than-competitive sales if unforeseen product flaws are found during testing, production, or worse, in the field. Team 4 will explore any opportunities to ensure that the design utilizes a minimum amount of material while eliminating possible design flaws that might cost more money for the customer to repair. Team 4 will also make every effort to ensure the final design is complete and easily assembled to avoid manufacturing and delivering complications that could drastically increase costs and lead to canceled orders.

2. Competition

Currently, there are no existing UAVs competing for the team’s target market. This is primarily due to the fact that there have not been any UASs seriously deployed in the civilian world. Though there are a small number of police agencies that currently own and operate small hand-launched UAVs, they are not being used to any appreciable extent for defined missions. The main competition would be from existing helicopter fleets. To successfully compete, the UAS would need to offer more than just a competitive ability to convince the customer to acquire a new, unproven aerial vehicle and replace the current and proven one.

According to market studies conducted by an industry watchdog, (Helicopter International Association), the five year average for 2000-20005 for new turbine helicopter sales to Law Enforcement agencies has been 40.2 per year making up a market share of 26.70 %. Figures 2.1, 2.2 and 2.3 below chart the trends in the numbers of helicopter sales to Law Enforcement and US Public Service agencies over the previous ten years.

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Figure 2.1: 10 year trend for new turbine helicopter sales to Law Enforcement Agencies in the US [2.4]

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Figure 2.2: Annual Turbine Helicopter Sales growth to US public service agencies 1993 – 2005

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Figure 2.3: Estimated current fleet of piston Helicopters in US law enforcement [2.3]

The market studies indicate an economic downturn in helicopter sales during the period immediately after September 11, 2001. However, by 2005, the sales growth was seen to return to the normal pace. Figure 2.4 below tracks the sales figures for all new turbine helicopters in the US over the 7 year period from 1999-2005. Team 4 could not obtain accurate figures for the number of helicopters in operation for News Gathering, so figure 2.4 should be an indicator for this portion of the market.

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Figure 2.4: 7 year trend for total new US turbine helicopter sales to US civil operators

The two most popular types of rotorcraft in use by News Agencies are the Bell 206 Jetranger and the Eurocopter AS-350. Other rotorcraft gaining in popularity are the McDonnell Douglas H-500, and Robinson R-44 due to their relative cost-effectiveness. [2.5]

Table 2.1, and figures 2.5 and 2.6 below show the trends for the acquisition and operating costs for various popular competing helicopters in current use.

|Aircraft |Acquisition Costs ($) |Hourly Operating Costs ($) |

|Bell 206B Jetranger |1,200,000 |795 |

|Eurocopter AS-350 |1,670,000 |495 |

|MD H-500 (used 1981) |475,000 |211 |

|Robinson R-44 |610,000 |164 |

| |

|Source: aeroads.ca/heliads/search.htm |

Table 2. 1: Competing Helicopter Acquisition and Operating Costs

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Figure 2.5: Acquisition Costs for various competing helicopters currently in use [6]

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Figure 2.6: Hourly Operating Costs for various competing helicopters currently in use [6]

The Metro-Scout UAS’s biggest advantage will be cost. By replacing the helicopter with the Metro-Scout, or supplementing current helicopter operations to lower helicopter flight hours, customers will save in operating and maintenance costs. After researching new and used helicopter acquisition costs from Bell helicopters (chosen because of their widespread use by our target customer) the team estimated that customers could expect to pay anywhere from 0.5 to 1.5 million dollars to purchase a new or used helicopter and payload capable of fulfilling their requirements. They would then spend anywhere from 0.2 to 0.5 million dollars a year in maintenance costs with operating costs averaging around $175/hr. [1] The team deduced that for a smaller, less complicated aircraft, operating and maintenance costs will be lower than that of a helicopter, though at this point in the design it is difficult to estimate how much lower that will be. To further compete, the team has set the goal acquisition cost of the Metro-Scout UAS competitive to the cost of maintaining a helicopter for one to two years, thus promising not only savings in the long run, but also an acquisition cost that is close to what the customer would be required to pay for maintenance costs for the current helicopter. The target acquisition cost that Team 4 has established for the Metro-Scout UAS is $350,000, with a target operating cost of $50.00/hour. Maintenance costs would average those of most general aviation aircraft at around $4000 a year.

3. Market Size

To estimate the market size, the team researched the existing number of helicopters operating in the United States. According to the Aircraft Owners and Pilots Association (AOPA) of America, there are approximately 7,000 civilian helicopters operating in the US. Of these, about 5,000 are privately owned. This was confirmed by the marketplace reports. The market letters reported that law enforcement agencies in the US had a total of 154 confirmed active piston helicopters, and 483 confirmed active turbine helicopters in use in the Fall of 2005. These numbers are representative of new helicopters sold to Public Service Agencies in the past 20 years and do not take into account the 797 military surplus turbine helicopters that US public service/Law Enforcement Agencies acquired from the US army between 1993 and 2002. However, the reports found that most of these military surplus helicopters have been serving as parts supply for operational helicopters, and Team 4 cannot derive a reasonable estimate for the number of active military surplus helicopters used in Law Enforcement. The net total for helicopters used by law enforcement today is in the 625-650 range. [2.3], [2.4]

Electronic News Gathering is the other target market for the team’s product. The two most popular types of rotorcraft in use by News Agencies are the Bell 206 Jetranger and the Eurocopter AS-350. Other rotorcraft gaining in popularity are the McDonnell Douglas H-500, and Robinson R-44 due to their relative cost-effectiveness. Team 4 estimated that the total number of active helicopters involved in news gathering was somewhere in the 200-250 range. The Team arrived at this estimate by looking at the number of big cities that might require news gathering helicopters. The team estimated conservatively about 100 cities in the US that would have a news market large enough for news helicopters. Also, the team estimated additionally that there are about 40 metropolitan areas in the US large enough to have two or more news agencies with a helicopter on stand-by at all times. [2.5]

From this, the team estimated that law enforcement and news agencies combined were flying approximately 900 helicopters in the US. This in itself is a sizeable market. However, the relative ease of operability and cost-effectiveness of the Metro-Scout design should make it attractive to a number of smaller News Agencies and Law Enforcement Agencies that cannot afford the cost of owning and operating helicopters. [2]

Team 4 attempted to develop a realistic prediction of the sales trend for the Metro-Scout Unmanned Aerial System over the course of its expected design life. The team estimated that the metro-scout UAS would need a minimum of 3 years for design, testing, and certification. Production is slated to start in the year 2010, with an initial sales estimate of 20 airframes. Team 4 estimated the sales trend from 2010 through 2021 on a classic model describing the introduction of new technology into the industry. Sales are estimated to increase nearly exponentially after the first year, as customers recognize the potential in cost-savings of acquiring the Metro-Scout UAS. The expected sales growth can be attributed to a number of News Agencies and Law Enforcement Agencies phasing out portions of their aging helicopter fleets in favor of the UAS. Also, the team expects smaller markets to open up in smaller metropolises in about 5-6 years. At this point, the market for the Metro-Scout model should have realized its full potential. Full-Scale production of about a 150 units will only occur around the year 2015, and sales will regress soon after. The reason for the regression is that other manufacturers will catch on to the market potential, and the Metro-Scout will start to become a less competitive option. The team expects this to occur in the 2017-2021 period. However the success of the first model would allow Team 4 to develop a newer more competitive UAS to compete with UASs design by other aircraft manufacturers as they come out. Table 2.2 below lists the expected sales figures in the period 2007-2010 for the Metro-Scout UAS. Figure 2.7 depicts the trend of marketplace technology acceptance, sales growth, realization of full potential, and sales regression expected over the next decade for the Metro-Scout product.

Table 2. 2: Anticipated Market Outlook for the Metro-Scout UAV

|Market Outlook (Expected Sales Figures) |

|  |

|Year |Metro-Scout Expected Sales |Expected Market Share (%) |Competing Helicopters Sold|Competing UASs sold |Total Market Size |

|2007 |0 |0 |50 |0 |50 |

|2008 |0 |0 |50 |0 |50 |

|2009 |0 |0 |50 |0 |50 |

|2010 |20 |30.77 |45 |0 |65 |

|2011 |50 |50.00 |40 |10 |100 |

|2012 |75 |53.57 |35 |30 |140 |

|2013 |100 |58.82 |20 |50 |170 |

|2014 |120 |63.16 |10 |60 |190 |

|2015 |150 |64.38 |8 |75 |233 |

|2016 |100 |48.31 |7 |100 |207 |

|2017 |85 |41.46 |5 |115 |205 |

|2018 |80 |38.10 |5 |125 |210 |

|2019 |75 |36.59 |5 |125 |205 |

|2020 |50 |27.03 |5 |130 |185 |

|2021 |40 |21.62 |5 |140 |185 |

|  |  |  |  |  |  |

|Total Sales |945 |533.80 |340 |960 |2245 |

|Yearly Average |63 |35.59 |22.67 |64 |149.67 |

[pic] Figure 2.7: Expected market trends for Metro-Scout Sales 2007-2021

As seen from figure 2.7, product acceptance in the marketplace is expected to occur in the period 2009-2011. From thereon, sales growth is expected to occur linearly till the full sales potential is reached around 2015. Sales are expected to then regress as the market receives an influx of newer more competitive UAVs. However, sales are still expected to continue to smaller News Agencies and Law Enforcement Agencies due to the Metro-Scout’s relative inexpensiveness by the period 2017-2021. Figure 2.8 below highlights Team 4’s expected general marketplace trends for the growth of the UAS market among our target customers. It is expected that the size of the UAS market will grow linearly before stabilizing around the year 2025.

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Figure 2.8: Expected Market trends for UAS sales to Law Enforcement and News Agencies

Team 4 reiterates that these are expected sales figures, and should be considered only potentially representative of the final success of the product. The final step of the team business case was to estimate total monetary returns on the Metro-Scout project. The team formulated an expression for product value depreciation over the years, and incorporated this into the monetary outlook. The team anticipates a net profit of around $195 million at the end of 2021, from the Metro-Scout program. The details of the monetary return and profits generated on all sales are listed below in Table 2.3.

Table 2. 3: Estimated Monetary Return on Metro-Scout UAS project

|Year |Metro-Scout Expected Sales|Expected Price Tag ($) |Monetary Return ($) |Production Costs ($) about |Net Profit ($) |

| | |with depreciation | |100k per unit | |

|2010 |20 |350,000.00 |7,000,000.00 |2,000,000.00 |5,000,000.00 |

|2011 |50 |350,000.00 |17,500,000.00 |5,000,000.00 |12,500,000.00 |

|2012 |75 |340,000.00 |25,500,000.00 |7,500,000.00 |18,000,000.00 |

|2013 |100 |330,000.00 |33,000,000.00 |10,000,000.00 |23,000,000.00 |

|2014 |120 |315,000.00 |37,800,000.00 |12,000,000.00 |25,800,000.00 |

|2015 |150 |300,000.00 |45,000,000.00 |15,000,000.00 |30,000,000.00 |

|2016 |100 |300,000.00 |30,000,000.00 |10,000,000.00 |20,000,000.00 |

|2017 |85 |290,000.00 |24,650,000.00 |8,500,000.00 |16,150,000.00 |

|2018 |80 |290,000.00 |23,200,000.00 |8,000,000.00 |15,200,000.00 |

|2019 |75 |290,000.00 |21,750,000.00 |7,500,000.00 |14,250,000.00 |

|2020 |50 |275,000.00 |13,750,000.00 |5,000,000.00 |8,750,000.00 |

|2021 |40 |275,000.00 |11,000,000.00 |4,000,000.00 |7,000,000.00 |

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|Totals |945 | |290,150,000.00 |94,500,000.00 |195,650,000.00 |

|Yearly Average |78.75 |308,750.00 |24,179,166.67 |7,875,000.00 |16,304,166.67 |

3. CUSTOMER ATTRIBUTES

The team chose to follow the industry culture of identifying and differentiating external and internal customers, and external regulating influences. We believe that using this culture of identifying parties that influence our design as customers, will help us better in defining our product design according to all of their requirements and constraints.

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Figure 3.1: Schematic defining and differentiating the team’s different Customers

What follows is a short description of each grouping of customers as defined by Team 4:

External Customers: These are the parties that the product will be marketed and sold to. They are the reason the product exists, and their design requirements take precedence where FAA regulations and laws allow.

Internal Customers: These are parties within the hypothetical company that the team represents that will be responsible for getting the product out the door and sold to the external customers. Traditionally, internal customers are the manufacturing and marketing departments of the company.

External Regulating Influences: These are the parties outside of the internal and external customers that have significant regulating influence over the final design of the UAV.

Sections 3.1 – 3.3 detail the attributes of each of the team’s target customers.

1. External Customer Attributes

Team 4’s External Customers are News Agencies and Law Enforcement Agencies. As such, their specific customer attributes get first priority where FAA regulations and local laws permit.

There are certain external customer attributes that are extremely important, such as fuel efficiency, long endurance, ease of maintenance, and low cost to name a few. A low cost UAV, for instance, will be essential to compete with current helicopters. In order to create a competitive UAV, costs needed to be kept low including acquisition, maintenance, and operating cost. In terms of performance, the aircraft will need to be fuel efficient. This in turn keeps cost down since fuel is currently expensive. Although high endurance will increase the amount of fuel needed, it is the premise of the previously described mission, therefore making it an important external customer attribute. There will also need to be high quality images taken and received for the described missions. This imaging capability will be a function of both the aircraft cruising altitude and the camera’s capabilities.

2. Internal Customer Attributes

Internal Customers primarily take the form of Team 4’s Manufacturing and Marketing departments. The needs of these internal customers will have to be satisfied if Team 4 is to design a financially successful product. To elaborate on previous statements, the primary reason for the team’s concern with internal customer attributes is the fact that the design will be Team 4’s, but the building and selling of the product will be the responsibility of the Internal Customers (the Manufacturing and Marketing people). It is important for the team to design the Metro-Scout to incorporate the requirements and needs of the Internal Customers. Team 4’s primary internal customer attributes include but are not limited to items like ease of manufacture through the use of proven technologies, ease of assembly, and ease of developing product marketing potential. Some of Team 4’s primary concerns during the design process are focused around incorporating these internal customer attributes into the Metro-Scout design.

3. External Regulating Influences

External Regulating Influences take the form of the FAA and the General Public.

The primary external regulating influence in the design is the FAA. The FAA will require a safely operated UAS, which meets all the current requirements. Such requirements include a high improbability of collision, compliance with cloud and terrain clearances, and a pilot in command at all times. This last regulation is of particular importance due to the nature of our missions. It is likely that in order to succeed in our mission capabilities, the need will arise for the project group to apply for a waiver to allow the use of an autopilot. This is certainly doable, as at least 50 UAVs have already successfully attained this waiver.

The General Public’s primary concern with the Metro-Scout UAS is focused around safety and pollution. Some of the questions that the team has received from members of the public are centered around the following: (1) Is it going to be safe to fly over populated urban environs? (2) Is it going to be able to avoid collisions with other aircraft and birds in the airspace it is flying in? (2) Is it going to be able to fly quietly? (4) Is it going to be incorporate emissions standards, either new or established?

Addressing all of these concerns in a manner that is satisfactory to the FAA and General Public will be very important to Team 4.

4. Quality Function Deployment (QFD)

The team used Quality Function Deployment as a method to negotiate the maze of different customer wants, and corresponding product engineering characteristics to determine what our product would ultimately be capable of in the final design. Essentially, it gave us a scientific means of being able to evaluate what features our design would incorporate, and what would have to be downplayed or discarded. The criteria listed on the left-most column of the QFD comprise the WHATs of the QFD – these are usually customer attributes that must be evaluated in terms of what the product is going to be capable of doing. What the product is going to be capable of doing are defined as the engineering characteristics, which are listed as the HOWs in the top row of the QFD. The engineering characteristics are quantifiable, and can therefore be used to establish the practicality of incorporating specific customer attributes into the UAV design.

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Essential to the interpretation of where each of the customer-defined and engineering-defined parameters fit into the overall scheme of the QFD is how each of them factor into the product’s overall concept of operations. (See section 4.0). A perfect UAV design for the mission requirements would be fast and yet capable of slow loiter, able to carry heavy payloads, be cheap and easy to manufacture, meet all FAA regulations, be quiet and have near zero emissions and be cost-effective to maintain and to acquire. From an engineering standpoint, achieving all of these goals to exacting customer needs is near-impossible. Finding trade-offs that would provide the best solution within constraints defined collaboratively by both the customers and the design team is Team 4’s primary goal, and the QFD chart shown above is very useful for establishing design priorities. The QFD identifies all the requirements of a UAV design that would have the functionalities required by News and Law Enforcement agencies that have traditionally relied on piloted rotorcraft. The Customer Attributes fit into one of four categories – Performance, Adaptability, Environment and Other.

The relative importance of each customer attribute was determined based on Team 4’s understanding of the customers’ priorities. A rank from 1 to 10 was assigned to each individual customer attribute based on its relative importance in the ranking scheme. A rank of 10 indicates highest importance, while a rank of 0 indicates minimal importance to the customer. Shown below, is an example of this ranking scheme for the ‘Performance’ Section of our Customer Attributes.

Table 3.1: Example of Customer Attribute Ranking

| |Customer Attribute |Importance |

|Perfor|High Endurance |6 |

|mance | | |

| |Fuel Efficient |10 |

| |Ceiling |1 |

| |Maneuverability |2 |

| |Efficient Climb |4 |

| |Payload Capacity |1 |

| |Low Stall Speed |5 |

| |Medium Range |6 |

Correlations were drawn up between each customer attribute and engineering characteristic, based on Team 4’s engineering wisdom as to the effect they would have on one another. Individual cells were assigned a numeric scores and a color code to show the extent of the correlation between customer attribute and engineering characteristic. Blank cells (Score -0) for instance, indicate no observed correlation. A score of 1 (color-code – Green) indicates minor correlation, while a score of 3 (color-code – Yellow) indicates moderate correlation. An assigned score of 9 (color-code – Orange) indicates a strong correlation. An example of the correlation method used is shown below for the Performance Section of the QFD matrix.

Table 3.2: Example showing Correlation Scheme used

|Performan|Customer Attributes |Engineering Characteristics |

|ce | | |

| | |L/D |Gross Wt. |SFC |

| |Medium Range |1 |

| | |L/D |Gross Wt. |SFC |

| |Importance (Relative) |0.304 |0.304 |0.391 |

Team 4 identified the most important customer requirements as Safe operability over highly-populated areas, fuel efficiency, ease of maintenance, and low acquisition and operating costs. In terms of engineering characteristics, these major customer requirements are seen to correlate strongly with the following engineering characteristics.

Table 3.4: Correlation between most important Customer Attributes and Specific Engineering Characteristics

|Major Customer Attributes |Correlated Engineering Characteristics |

|Safe Operability over Populated terrain |Stability (+) , Loading Capacity (+) |

|Fuel Efficiency |SFC (+) , Low Drag Coefficient (+) |

|Ease of Maintenance |Design Lifetime (+) |

|Acquisition Costs |Thrust to Weight Ratio (-) |

|Operating Costs |SFC (+), Real-Time Data Relay to PIC/operator (+) |

|Continuous Area Coverage |SFC (+) , Drag Coefficient (+) |

The last step of the QFD was to establish design targets and benchmark scores for each of the Engineering Characteristics. The benchmark aircraft used were the Bell JetRanger and the Pioneer UAV. These were selected as benchmarks based on the similarity of their designed-for mission requirements to team 4’s mission requirements. The design targets were based primarily on the need to compete with these benchmarks, and also from data gathered through trade studies and the team’s initial sizing estimates.

4. CONCEPT OF OPERATIONS

The UAV will be maintained at and operated from a small local airport in the proximity of the police or news station. This will allow the craft ample room for takeoff and the operators convenient access to the plane. Airport employees or personnel contracted by the respective owners will maintain the aircraft (fuel, pre-flight inspection, other routine maintenance, avionics check) while personnel from the police or news station will be in charge of the payload equipment (cameras, infrared, lights).

The UAV will accomplish three basic types of missions: long-range coverage, high-endurance coverage/surveillance, long-range pursuit. Long-range coverage pertains mainly to news station affiliates looking to cover events occurring a distance of greater than 40 miles from the airport at which the UAV is housed. High-endurance coverage consists of long periods (4 hrs or more) of loitering over an event for live, continuous coverage of an area (i.e. sporting events, traffic patrol). Both police and news organizations will perform this type of mission. Long-range pursuit encompasses the chasing of a suspect in a ground vehicle over a long distance, usually at high ground speeds. This mission proves vital for police, but news stations often cover these chases in the same matter. The Mission Analysis section contains an example of this type of mission, as well.

Long-range coverage reduces the amount of coverage of an event due to the high amount of fuel consumed flying to and from the location. When the UAV is deployed for this type of mission, it will most likely fly to the event, obtain anywhere between one-half and one and one-half hours-worth of film, then return to base for refueling. The aircraft will need a range of at least 300 miles to cover an area comparable to that of the helicopters that represent its competition.

High-endurance coverage represents the mission most commonly used by both police and news organizations. The Mission Anlsysis section lists an auto race as a situation for this type of coverage due to the crowd control issues and large area of impact such an event spawns. Other examples of this type of mission include traffic patrol (catching speeding vehicles on camera), coverage of a hostage situation or standoff, and large fire coverage. The UAV should be able to loiter over these events for four or more hours to provide continuous coverage before having to return to the airport to refuel.

Long-range pursuit involves pursuing a suspect or event over a long distance and, most likely, at high speed. Suspects evading police authority are usually pursued not only on the ground but also in the air. The UAV will provide real-time images of the suspect that can be used to alert ground forces of the suspect’s location and provide TV viewers with live pictures of the pursuit. The UAV will maneuver to pursue the suspect’s vehicle should it leave the road or attempt to make sudden changes in direction that might elude ground forces. It will also have search tools such as infrared for night or low-light pursuit of the suspect while he or she is on foot. An example of this type of mission can also be found in the Mission Analysis Section.

Dual-mode control constitutes an important attribute of the UAV. The UAV will have the ability to operate autonomously over a given area using certain waypoints (such as when patrolling a specific area for traffic), but a remote pilot located at the news or police station will do much of the flying for other missions A news or police designated employee will remotely operate the camera though it can be autonomously operated. At any point in an autonomous flying configuration, however, a pilot will be able to take control of the aircraft.

An option to be explored by potential customers is a second or third UAV to use in addition to the first. In cases such as long-range or high-endurance coverage, this will allow for longer periods of continuous coverage because one UAV can enter the area of surveillance before the other one leaves to refuel.

4.1 Mission Analysis: Case 1 – Long Range Coverage

The following mission example originates in Indianapolis, IN, at Eagle Creek Airpark (Figure 4.1)[4.1]. This airport has a runway of length 4200 feet.

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Figure 4.1

Customer: Indianapolis News Affiliate

Situation: Ten-car accident has shut down I-65 just 3 miles south of Lafayette exit

Roll: Record footage of the accident as close to the time of crash as possible and as emergency vehicles arrive

Itinerary: 10:50 AM – News station notified of accident

11:05 AM – Depart from Eagle Creek Airpark (general aviation, low-traffic airfield) in Indianapolis for accident site 60 miles northwest at cruise of 100 kts

11:45 AM – Arrive at accident site; slow speed for best loiter and circle the site at around 1,000 ft for best aerial coverage; relay footage to station for taping

12:05 PM – Relay live feed to station for noon newscast

12:40 PM – Depart crash site for Indianapolis at 100 kts

1:25 PM – Arrive and land at Eagle Creek Airpark for refueling and await next call

4.2 Mission Analysis: Case 2 – High Endurance Coverage

The following mission example originates in Indianapolis, IN, at Eagle Creek Airpark (Figure 4.2)[4.1]. This airport has a runway of length 4200 feet.

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Figure 3.2

Customer: Indianapolis News Affiliate/Indianapolis Police Department

Situation: Traffic surrounding the Indianapolis 500 requires monitoring before and after the event

Roll: Provide aerial views of streets and parking lots within a two-mile radius of the venue at peak traffic times (before and following the race)

Itinerary: 6:00 AM – Depart Eagle Creek Airpark for Indianapolis Motor Speedway 3 miles East at best loiter speed, which will be used throughout the flight

6:05 AM – Arrive at IMS; slow speed and circle area within two-mile radius of track, changing altitude at various times for a closer view

9:00 AM – Return to Eagle Creek Airpark for refueling

9:20 AM – Depart Airpark for IMS

9:25 AM – Arrive at IMS and repeat same functions as before

12:00 PM – Return to Airpark for refueling (In police function, would most likely return to air and previous duties. In news function, would remain at Eagle Creek as race has started and traffic is at a minimum)

3:00 PM – Depart Airpark and return to event site and previous crowd and traffic duties

6:15 PM – Return to Airpark and await next call

4.3 Mission Analysis: Case 3 – Long Range Pursuit

The following mission example originates in Indianapolis, IN, at Eagle Creek Airpark (Figure 4.3)[4.1]. This airport has a runway of length 4200 feet.

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Figure 4.3

Customer: Police Department/State Police

Situation: Suspect in hit-and-run is evading squad cars on high speed (70-100 mph) chase that begins on urban interstates and continues into rural areas

Roll: Provide aerial pursuit, keeping pace with and relaying suspect’s position to pursuing authorities below

Itinerary: 5:15 PM – Receive call for aerial pursuit of suspect vehicle on urban interstate

5:25 PM – Depart airport and fly toward suspect’s current position

5:32 PM – Confirm visual contact of suspect vehicle and continue pursuit at around 80 mph and 1,000 ft. to avoid urban structures such as high-rises and radio antennae

5:40 PM - Continue pursuit through suburban areas as suspect increases speed to around 90 mph, maintaining altitude; continuously relay suspect’s position to ground pursuit

5:55 PM – Continue pursuit as suspect increases speed to around 100 mph into urban areas; able to descend if necessary

6:00 PM – Suspect exits interstate and continues to evade authorities through fields and country roads; continue pursuit and use infrared if suspect exits vehicle and begins to flee on foot

6:10 PM – Suspect apprehended; return to airport at best cruise speed of 100 kts and cruise altitude

6:40 PM – Arrive back at airport for refueling; await next call

[pic]

Figure 4.4

5. CURRENT DESIGN REQUIREMENTS

1. Payload

Different payloads are required for the different missions designed for the law enforcement agencies and the news agencies. These payloads were created based on the concept of operations described above and the different customer attributes requested.

Table 5.1 lays out exactly what pieces of equipment are compiled to make up the payload package that will be sold to law enforcement.

|Package |Payload |Weight(lb) |Dimensions(ft) |

|Police package |Radar gun |1 |0.505 x 0.194 x 0.453 |

| |  |  |  |

| |Camera gimbal |51 |.917X1.25 |

|  |  |  |  |

|  |ThermaCAM SC3000 |7 |mounted on gimbal |

|  |Sony DSR-PD150 (video cam) |3.1 |mounted on gimbal |

|  | | | |

|  |Canon powershot S3 IS ( still camera) |0.904 |mounted on gimbal |

|  | | | |

|  |Canon lens f/4.5-5.6 II USM |0.684 |on camera |

|  |Autopilot |0.1875 |.34 x .17  x .14 |

|  |  |  |  |

|  |Total weight |63.8755 |  |

Table 5.1:Payload Package for Law Enforcement[1],[2],[3],[4],[5],[6],[7]

During highway patrols for speeding vehicles, the Metro-Scout will fly at the speed limit set for the highway and any car moving faster than the UAV will trigger the radar gun to record the exact speed of the speeding vehicle. This in turns triggers the still camera to snap a picture of the vehicle’s license plate. Law enforcement officers can then issue the violators a ticket and mail it to them.

In search and rescue operations, the video camera, infrared and still camera will work in tandem with one another. If the infrared camera detects a possible target, the video and still cameras will be used to positively identify the target. These images are then sent back via live feeds through a transmitter.

The radar gun is one of the most essential pieces of equipment in the payload package designed for law enforcement. When calculating the speed of a moving car, it has an accuracy of 1.25 miles per hour and is able to “measure a target speed ranging from 2.5 miles per hour to 82 mile per hour. Relative position of the target in front of the Metro-Scout does not matter. The radar gun can take an accurate reading on any vehicle that is within 90 degrees to the left or right of the nose of the UAV. This particular radar gun was chosen for this payload package because it weight less than one pound. The correct evaluation of speed is guaranteed by Semicon. [5.1]

The camera gimbal has a 4-axis gyro stabilized video system. It is able to rotate 360 degrees and track stationary and moving targets from up to 3000 ft. [5.2] The camera operator can control the gimbals’ system which then transmits the video feeds and still images through microwaves back to the ground.

The ThermaCAM is an infrared camera coupled with its software can provide live feeds of an extensive temperature range. It is able to measure extremely small and distant targets with great accuracy (±1%) and high resolution. [3] This will assist law enforcement in criminal pursuit during the day and even at night. In the event that the suspect is hidden from view of a regular camera, the infrared can detect the heat signature of the suspect. This infrared camera is also relatively light at seven pounds, providing an additional capability which aids the capture of criminal suspects.

The video camera is also mounted on the gimbal. The Sony DSR-PD150 has a build in image stabilizer with a 12 X optical and 48X digital zoom. [4] This camera will be able to provide close up aerial videos from the air. This camera is also very light, weighing 3.1 pounds.

A high resolution still camera is also essential for law enforcement agencies. The Canon powershot S3 IS will be equipped with a 50-200mm lens that will be able to take high resolution still images of license plate numbers from up to a distance of 3000 ft. [6] This camera can also be used by law enforcement to take high quality pictures of evidence against fleeing suspects.

The autopilot software for the UAV is capable of flying at a maximum altitude of 16,000 ft above sea level and a maximum airspeed of 150 mph. It comes with a transmitter to broadcast airspeed, pressure and temperature to the ground in compliance with FAA regulations.

Table 5.2 shows the contents of the payload package for the news agencies.

|Package |Payload |Weight(lb) |Dimensions(ft) |

|News Station/filming |Cineflex V14 |67 |1.21 X 1.63 X 1.63 |

|package | | | |

| |  |  |  |

| |Autopilot |0.1875 |0.34 X 0.17  X 0.14 |

| |  | |  |

| |  |  |  |

| |Total weight |67.1875 | |

| | | | |

Table 5.2: Payload Package for News Agency [7],[8]

This package is very different than the package designed for law enforcement. There are a number of components that have been removed. The camera for the news station allows for high definition live video feeds. This camera weighs more than the entire payload for the law enforcement as it is a high definition filming camera mounted on a gimbal. The Cineflex camera is also currently mounted on helicopters and also used for filming movies. The built in wide angle view and infrared cameras allow for filming at all times of the day. Lastly, the Cineflex also has a 25 X zoom enabling aerial footages to be filmed from up to 3000 ft. [8]

2. Constraint Analysis

The performance analysis, in most cases, answers the question of whether a particular aircraft design will meet a customer’s needs. The process of constraint analysis is to narrow down the choices of the many interrelated variables to control and make choices to which design an aircraft that will have desired performance capabilities. Constraint analysis calculates ranges of values for an aircraft concept’s take-off wing loading and takeoff power loading, which allow the design to meet specific performance requirements.

The constraint analysis is based on a modification on equation 1 for specific excess power

[pic] (1)

In equation 1, T/W is the thrust to weight ratio, D is drag, V is velocity, dh/ht is the altitude derivative and dV/dt is the velocity derivative. By substitute equations 2, 3, 4 and 5 into equation 1 the new constraint equation is stated in equation 6.

[pic] (2)

[pic] (3)

[pic] (4)

[pic] (5)

[pic] (6)

In equation 2, [pic] is the thrust lapse ratio which depends on the density ratio[pic]. In equation 3, [pic] is the weight fraction for a given constraint. This fuel fraction is necessary because the weight loss from the fuel has to be taken into consideration at every moment throughout the flight. Equation 4 is the equation for the lift coefficient. Equation 5 is the drag equation based on the lift coefficient found in equation 4. Equation 6 is the newly defined power equation for take-off weight. [5.9]

Takeoff Constraint

While equation 6 models in-flight performance, the takeoff constraint requires a different equation to calculate. Assuming[pic], equations 7, 8, and 9 are written below. [pic] (7) [pic] (8)

[pic] (9)

Rewriting equation 6 using equations 7, 8 and 9, equation 11 is the new power equation in terms of power loading, equation 10, and wing loading. This equation relies on the assumption that lift is approximately zero prior to rotation.

[pic] (10)

[pic] (11)

The unit of power in the above equation is horsepower. These equations also assume that lift is approximately zero prior to rotation.

Sustained Turn Constraint

Maximizing thrust loading and lift to drag ratio (L/D) maximizes the load factor in a sustained turn. At max L/D, the coefficient of drag is[pic], therefore deriving equation 12. [pic] (12)

Equation 12 is the wing loading equation for the max range and max prop loiter for a propeller aircraft. This equation proves that as weight reduces due to fuel burned, the wing loading also decreases during cruise. Optimizing cruise efficiency while wing loading is decreasing requires the reduction of the dynamic pressure by the same percent as seen in equation 12. The concept of max L/D and the above wing loading equation yields equation 13; the available thrust equation.

[pic] (13)

Constraint Results

By running Matlab code developed by team members, the group determined a design point for power loading and wing loading. Figure 5.1 shows this design point in terms of a specified power loading and wing loading value.

[pic]

Figure 5.1

This point represents a ratio of power loading to wing loading that best blends the loiter turn, max speed turn, and takeoff constraints. It does not necessarily optimize any of these constraints, but rather suggests a point where changing one constraint would unsatisfactorily affect another. Table 5.3 displays this optimum design point.

|Power Loading |0.05 hp/lb |

|Wing Loading |30 lb/ ft2 |

Table 5.3: Power Loading and Wing Loading Data

The sizing process uses this result to determine other parameters.

3. Sizing

Sizing is the process to determine how large the aircraft must be to carry enough fuel and payload to perform the design mission. A crude estimate of the maximum L/D is obtained. Specific fuel consumption was taken to be 0.4 and 0.5 lb/hr/bhp for cruise and loiter respectively [5.1]. Since empty weight is calculated using a guess of the takeoff weight, it is necessary to iterate towards a solution. The team has developed a Matlab program to calculate the total takeoff weight.

Fuel Fraction for Cruise and Loiter

The total gross weight equation is based on the fuel fraction and the empty weight fraction. Both of these equations are based on the L/D. The L/D equation shown in equation 14, is derived on the premise that parasite drag is not related to lift and the coefficient of drag is just[pic].

[pic] (14)

The fuel fraction and weight equations derived from the Breguet equation for cruise and loiter, used to find the total gross weight, are shown in equations 15 and 16 respectively.

[pic] (15)

[pic] (16)

In these equations R is range, E is endurance, Chpb is the specific fuel consumption for propeller aircraft. Eta P is the propeller efficiency; in most cases it is estimated at 0.8, or 80% efficient. [5.9]

The aircraft weight is calculated through out the mission. For each segment the aircraft weight is reduce by fuel burned. Total fuel burned is summed through out the mission and found by summing the weight fractions from each flight segment in equation 17.

[pic] (17)

In this equation 6% fuel is added for landing, takeoff, taxi and reserve. Equation 18 is the takeoff weight equation.

[pic] (18)

This equation is a summated of the different weights calculated from the various fuel fractions. [5.9]

Using data collected from the above analysis, table 5.4 is a compiled table of the initial sizing constraints.

|Total Aircraft Takeoff weight |590 lb |

|Fuel Weight |140 lb |

|Payload Weight |63.1 lbs |

|Aircraft Inert Weight |380 lb |

|Engine Power |53 HP |

|Wing Area |21.7 ft2 |

Table 5.4: Initial Sizing Data

4. Trade Studies

Takeoff Weight vs. Payload Weight:

[pic]

Figure 5.2

There are three graphs shown in the plot above. Each graph represents different endurance time with constant range at 500nm. The graph shows that takeoff weight, and therefore payload weight, increases as endurance increases. The design endurance, stated by the customer, was set at 5 hours. Setting 3 hour and 7 hour endurance time as the minimum and maximum, respectively, the aircraft estimated takeoff weight should fall within the area enclosed by both graphs.

Takeoff Weight vs. Range:

There are four graphs included Figure 5.3. Each graph represents different payload weights with different endurance times. Since the payload weights (63.19 and 67.19 lb) are fixed, for 5-hour endurance time, the estimated aircraft takeoff weight should fall within the area enclosed by the purple and red graphs and so the same for 7-hour endurance time with green and light blue graphs at the top.

For each of the four payload and endurance configurations, takeoff weight begins to drastically increase at a range of about 580 nm. This demonstrates that Metro-Scout’s range will most likely be slightly less than this distance. Such a range compares well with helicopters used for similar functions as the Metro-Scout. Modifications to increase range to the desired value of 600 nm are also possible.

[pic]

Figure 5.3

Takeoff Weight vs. Endurance:

[pic]

Figure 5.4

Figure 5.4 displays the variance in endurance with takeoff weight. For both payloads represented, takeoff weight increases quite linearly with endurance until endurance reaches ten hours, where takeoff weight begins to drastically increase. Thus, the team expects a maximum endurance of around nine to ten hours to be possible for these configurations based on current initial sizing codes.

The team could conduct other trade studies, but, for the time being, target values are set near (but not directly at) desired values. The group needs to pursue further calculations and trade studies to determine the optimum values that satisfy the business design requirements.

Metro-Scout compared with Pioneer.

For the first step of initial sizing, a table of comparison is shown below with Pioneer, a tactical military UAV. The Pioneer has about the same payload weight and ceiling as the Metro-Scout’s initial design:

| specifications |Metro-Scout |Pioneer |

|gross/takeoff weight (lb) |590 |452 |

|payload weight (lb) | 63.2 |75 |

|wing loading | 30 |22.3 |

|engine number/type | Piston prop engine |1 piston engine |

|installed thrust/power (hp) |53 |27 |

|maximum range (nm) | 500 |130 |

|maximum endurance (hr) | 6 |4 |

|cruise velocity (kts) | 50 |65 |

|maximum velocity (kts) |110 |110 |

|ceiling (ft) | 15000 |12000 |

Table 5.5: Comparison of Metro-Scout to Pioneer UAV [5.9]

5. Project Timeline Description

[pic]

Team 4 elected to develop a project timeline to establish a baseline measure of progress through the course of the semester. Team 4 has specifically targeting a number of phases in the design for overlap to allow the team greater freedom to make design changes and foster greater customer participation in formulating design requirements. For instance, the project timeline shows that Customer Attribute Identification phase goes hand in hand with the Initial Conceptual Design phase until the date of the Systems Requirements Review whereat all the customer attributes need to be finalized. The same is true for certain aspects of the Initial Conceptual Design and the Design Analysis and Tweaking phases. The premise behind the layout of the timeline is to establish constraints and deadlines that keep Team 4 moving forward in the design process while giving it the freedom to make changes as deemed necessary to keep the project competitive. The five main stages in Team 4’s timeline and their current progress are –

1. Establish Customer and Product: Phase Complete

2. Customer Attribute Identification: Phase Complete

3. Initial Conceptual Design Phase Active

4. Design Analysis/Tweaking Planned/Not Active

5. Design Finalization Planned/Not Active

6. SUMMARY

Thus far Team 4 has determined to provide a primary customer based comprised of police and news organizations with the Metro-Scout, an unmanned aerial vehicle capable of performing those tasks for which those customers currently use conventional helicopters. This craft will perform both autonomously and with a remote pilot, depending on the mission. To perform such objectives, the team has determined key design attributes such as safe operation at 1000-1500 ft above ground level, a range of 600 nm, an endurance of at least five hours, and a payload weight of between sixty and seventy pounds. The group aims to sell the Metro-Scout to target customers at a lower acquisition and operating cost than current helicopters so as to be competitive within the market.

The next step forward in the design process involves several elements. First, the team must establish design parameters such as takeoff weight, thrust-to-weight ratio, engine package, and main airfoil selection for the wings. Another outstanding issue involves FAA regulations. Current FAA restrictions require a pilot to be in command of the UAV at all times, making autonomous flight illegal. The FAA suggests that obtaining a waiver for such flight could be possible, and because the Metro-Scout will not come to market within the next three years, ample time for FAA modifications and waivers exists. Along with these issues, the team must consider maintenance and production costs. With these items in mind, the group can continue in moving the product toward market.

7. REFERENCES

[2.1] "Bell Helicopter Commercial." 2007. Bell Helicopter Textron Inc. 28 Jan. 2007 .

[2.2] AOPA, “AOPA’s 2006 Aviation Fact Card”, download.epilot/2006/factcard.pdf [retrieved 18 February 2007].

[2.3] “The Helicopter Market Newsletter Piston”, Helicopter International Association, published Nov. 28th, 2005, [retrieved February 18th, 2007]

[2.4] “The Helicopter Market Newsletter Turbine”, Helicopter International Association, published Oct. 25th, 2005, [retrieved February 18th, 2007]

[2.5] Clark, Larry K., “The Life of a Pilot Flying ENG (electronic news gathering),” (online), 2/21/2004, , [retrieved February 15th, 2007]

[2.6] “2000 Aircraft Industry Studies”, The Industrial College of Armed Forces, , [retrieved Feb. 15th, 2007]

[3.1] Clausing, Don., Total Quality Development, ASME Press, New York, 1994

[3.2] Clausings, Don., Hauser, John R., “The House of Quality”, IEEE Engineering Management Review, Spring 1996 [Note: Vol no. and page no. not available]

[4.1] Google Maps. 26 Feb. 2007 maps

[5.1] “Mobile police radar gun” simicon specifications page [Retrieved 10-Feb-07].

[5.2] “Pixel 275 III” polytech specifications page [Retrieved 10-Feb-07].

[5.3] ThermaCAM® SC3000 Flir Systems therma cam specification page

[Retrieved 10-Feb-07].

[5.4] Hal, “Sony Dvcam DSR-PD150 DV Specifications” product wiki database [Retrieved 10-Feb-07].

[5.5] ”3400 Full featured UAV autopilot” 3400 Auto pilot specifications 3400autopilot.html [Retrieved 10-Feb-07].

[5.6] “Specification PowerShot S3 IS” S3 IS specifications [Retrieved 10-Feb-07].

[5.7] ”Specifications EF 55-200mm f/4.5-5.6 II USM” EF f/4.5-5.6 II USM specifications

[Retrieved 10-Feb-07].

[5.8] “C I N E F L E X V 1 4 M A G N U M - M U LT I S E N S O R” Cineflex 14 M Specifications [Retrieved 10-Feb-07].

[5.9] Raymer, Daniel P, Aircraft Design: A Conceptual Approach, 3rd ed., Reston, VA 1999

[5.10] Aftergood, Steven, “Pioneer Short Range (SR) UAV” Federation of American Scientists. 05 March 2000 [retrieved 13 January 2007]

A.0 Appendix

A.1 UAV Database

Database sources:

shephard.co.uk/UVonline

irp/program/collect/uav_roadmap

pentagon/uavs





navy.mil

-----------------------

Ext. Regulating Influences

Design Requirements

External Customers

Internal Customers

News Agencies,

Law Enforcement Agencies

FAA

General Public

Manufacturing,

Marketing

Sara Tassan

John Thornton

Sean Woock

Alvin Yip

EAGLE CREEK

AIRPARK

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