Eclipse 500 VLJ Talk given at the Santa Clara Airmen’s Association www.sccaa.com Winfried W. Wilcke May 2006
Acknowledgements • The following sources of information and images are gratefully acknowledged: • Eclipse Inc. www.eclipseaviation.com • AOPA Magazine (July 2005 issue) • 'Aerodynamics for Naval Aviators' (USGovt) • 'Gas Turbine Engines' by R.E.Birch • 'B737 Cockpit Review' (Canova Pub.) • see also Wall Street Journal, May 6,2006
Flying the Eclipse ? • I haven't flown the Eclipse myself (yet) • Read Dan McElroy's (Delta Captain) fascinating AOPA article on how he and his family,all pilots, test-flew the Eclipse: http://www.aopa.org/pilot/eclipse
Jets versus Pistons • Physics 101 explains key differences between a jet plane and a piston plane • Bear with me through a few formulas • after all, we are Silicon valley geeks, no ?
Thrust = Recoil v m
Physics 101 • Momentum p = mass * velocity p = m*v • Force F = momentum change/time F=dp/dt • Work W = Force * distance W=F*x • Power P = Work / time P=W/t Thrust is created by changing the momentum of an air-mass: the jet or the propeller accelerates the airmass from v1 to v2. (v1 is the airspeed of the plane.) It's like shooting a rifle - thrust is nothing but the recoil from accelerating the air. v2 AirMass V1
Thrust and Massflow (prop or jet) The same thrust F can be achieved by a big airflow Q and a little velocity difference - think helicopter rotor or propeller plane - or a little airflow Q and a big velocity difference - think turbojet - For geeks: = 0 Force (Thrust) F = dp/dt = d(mv)/dt = v*dm/dt + m*dv/dt = m/t * (v2-v1) m/t = Q is called the 'mass flow' or 'airflow' Q = mass of air (in kg) inhaled by the engine (or engine/prop combo) per second, thus: F = Q * (v2-v1)
Power needed to create Thrust.. Kinetic Energy E: E = ½ m v2 where v = v2-v1 is the speed difference imparted by engine/prop PowerP = E/t = ½ m v2 / t = ½ Q ( v2 - v1)2 Power P goes up like the squareof the velocity imparted to the airstream by the engine or engine/prop, wheras thrust F only goes up only linearly with the velocity imparted. … This is really bad news for a jet: because of fundamental conservation laws of physics, a jet generally is basically inefficient, compared to a prop engine!
So - why a jet? Speed!! Jets Total Propulsive Efficiency At high speeds, the prop itself becomes very inefficient and a jet (or rocket) is the only choice ! (aka: conservation laws don't tell the whole story) Prop AIRSPEED
TurboJET Engine V1 V2
TurboFAN • Turbofans are ducted hybrid jet/prop systems - see earlier discussion on efficiency. All modern "jets" are turbofans.
Turbofan 747 Jet core Ducted fan ("propeller")
Fan Compressors Turbines
Horsepower of a Jet Aircraft • Jet Horsepower HP is proportional to speed • jet thrust is nearly constant with speed • HP = Thrust (lbs) * speed (knots) / 325 • Q: how much thrust does a Bonanza (250 prop-HP) at 162.5 knots develop ? • A Boeing 747 at full throttle runup - brakes set - develops ZERO horsepower • What's the HP of an Eclipse ? Be patient... Bonanza Answer : 325/162.5*250=500 lbs
Climb vs. Airspeed JET HP Power HP needed ~ v3 PROP HP Jets climb best at rather high airspeeds. We'll never see a jet bush plane ! Airspeed Best climb speed prop Best climb speed jet
Eclipse 500 Specifications • Cruise 375 knots • Range 1300 nm + NBAA (100nm +45min) reserves • Service Ceiling 41,000’ • 5 or 6 seats • Gross 5680 lbs (w/ 230 Gallons JetA) • 2200 feet takeoff/landing distance at SL (Pt 91) • Fuel flow 65 Gallons/hour (total) FL 330 • Stallspeed 67 knots - only!!
Eclipse Horse Power • 2x PrattWhitney 610 @ 900 lbs thrust ea • 375 knots * (2* 900 lbs) => 375*1800/325= 2077 HP ?? • Nope - unfortunately not that simple • 900 lbs thrust is at sea level, and jets loose thrust at altitude - and 375 knots is not achievable (or legal) at sea level • expect 40% of sea-level thrust at FL 330 ==> • 2077 HP * 40% = 830 HP • bummer, just lost 1247 HP of bragging rights ! • anyone in Eclipse who can get us the real numbers ?
AOPA ~ $1.7M (2008)
AVIO PFD • Primary • Flight • Display
Systems (1) • Sidestick control via pushrods & pulleys • no fly-by-wire • I wouldn't have bought it with fly-by-wire b.s ! • Friction stir welded aluminum structure • AVIO ‘operating system’ with 3 displays • No mechanical gauges except compass • Integrated Megitt autopilot • Landing gear = variable speed break
Systems (2) • Weather radar • WXM weather dowloads • Terrain database • Maintenance disk (10 MB sensor data/hr) • Vapor cycle air-conditioning • if A/C goes out at FL 390, cabin temp will reach 450 oF. A/C not optional in flight levels. • Wet wings (1540 lbs JetA = 230 Gallons)
Systems (3) • Centralized electronics in pressure vessel • 5-bus, all electric power • 2 batteries, 2 alternators • Electronic Power Distribution System • 2 mechanical +127 electronic circuit breakers • No hydraulics except brakes • Synoptic screens for single pilot operations
Typical Jet Starting Procedure • Throttle closed • Start lever closed • Fuel&boost pump ON • Arm starter master • Engage starter, N2 • Confirm N2,N1 rotating • 15% N2, open start lever • Light up at 18% N2 • Monitor EGT RATE of rise • 38% N2, starter off • 40% start lever closed • Idle at 55% N2 • Starter master off N2 N1 N2 system driven by starter. N1 not directly involved
Mandatory Training • Jet-type rating via United Airline Academy • Stapleton airport, Denver, CO • One week total immersion training • For new jet jockeys, less for experienced drivers • Minimum requirements • IFR, ME, high altitude physiological training • Pass entrance exam in modified B737 sim • 2 hour upset training (L39 warbird trainer) • FAA Examiner for type rating’s flight • to APT standards
Insurance • Mentor pilot mandatory for new jet pilots • 50..100 hours • type rating cost for mentor pilots ~ $8000 • type rating for anyone ~ $12,000 • USAIGC guarantees insurance • $25k … $46k / year (depending on jet hours)
Visit to Albuquerque March 2006
Manufacturing Albuquerque Factory Floor AOPA Magazine Images. July 2005 Friction Stir Welding
Flight Test Center AOPA Magazine July 2005
Integrated Test Stand AOPA Magazine July 2005
Reliability Architecture • 2000 flight hours/year target (!!!) • Eliminate: hydraulics, thrust reversers • Use: stepper motors, central dual avionics inside pressure vessel,LED, brushless motors,. • 300 & 1200 hour inspections • Engine: 3500 TBO • With 1750 hours Hot Section Inspection
Your's truly, after writing a big check. I hadn't planned on putting a deposit down yet, but then I found a crumpled old blank check in my wallet and used it. It's dangerous to visit the Eclipse factory!
So what will that sweet smell of kerosene cost me ? • Baseprice $1.295 Million (2000 dollars) • but increases linearly w/ consumer price index • Estimate base $1.7 Million (late 2008) • plus options, 8.25% tax…
It is pretty cozy, about the size of a mini-van interior
Total @ 100 hours/year • JetComplete $115 (all numbers per hour) • Fuel $240 (@ $4/gallon, 60 gph) • Insurance $400 (initally) • Hangar $90 (E16 large T-hangar) • Tax $170 • Total $1015 / hour (~ $100k/year)
Free Flight • NASA visionary Dr. Bruce Holmes • Author James Fallow ( Free Flight) • 400 US airports for scheduled airlines • out of 13000 public US airfields • 5000 suitable for Eclipse (w/ GPS & WAAS) • Vision of airtaxi industry • Avg airline trip length 400 nm • 75% of US lives @ 30 min of suitable airport • 15000 VLJ by 2015 ? • Dayjet CEO "our competition is the car, not airlines "
History of Eclipse Aviation • www. Eclipseaviation.com • Founder Vern Raeburn • Microsoft, Lotus, Symantec, Paul Allen’s co. • $400M raised (mostly Allen & Gates) • 8 year history • Planned to use (new) Williams F22 engine • discarded after first flight...
And if all else fails…. Google turbinenuts