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HomeMy WebLinkAboutOB 1 CARVER DEVELOPMENT - TENTATIVE PARCEL MAP 85-246OLD BUSINESS 'AG E N l� NO. 1 V^ �• 9-16-85 DA,�rl _44� DATE: SEPTEMBER 9, 1985 j Inter - Com TO: WILLIAM HUSTON, CITY MANAGER BOB LEDENDECKER, DIRECTOR OF PUBLIC WORKS/CIT __1 ` � � � � y1° � � •-' �� L_ FROM: Y ENGINEER SUBJECT: CARVER DEVELOPMENT - TENTATIVE PARCEL MAP NO. 85-246 RECOMMENDATION: That the Tustin City Council, at their meeting of September 16, 1985, deny the request of Carver Development for relief to Condition of Approval II -1-d and adopt Resolution No. 85-88 as recommended by the Planning Commission. Raryr.pnIINn On September 3, 1985, Carver Development appeared before the City Council requesting relief from Condition II -1-d of proposed City Council Resolution No. 85-88 which when adopted would approve Tentative Parcel Map No. 85-246. Due to the lateness of receiving all of the back-up data from Carver Development and City staff, a full package of material was not available to the Council on September 3rd. This information is attached with this memo and is described as follows: ° Carver Development submittal identified as letter from Crain and Associates of Southern California dated August 27, 1985. Carver Development submittal identified as letter from Donald Frischer and Associates dated August 27, 1985. ° Kawamura memo with collision diagram dated August 29, 1985. Copy of the channelization design standards from the CalTrans Planning Manual. An additional diagram is attached which depicts the requested modifications to the southwest corner of Main St. and Newport Ave. and the resulting loss of building area within Building No. 3. DISCUSSION: During the initial preliminary site plan reviews, staff has addressed the need for modification of the geometrics of the southwesterly corner of Main St. and Newport Ave. to facilitate future traffic increases due to development within the City and regional areas surrounding the City. As the site plan was processed for approvals, this request for modification was not addressed by the developer on the basis that they felt it was not needed. The site plan was then approved by the City without this need being addressed. SEPTEMBER 9, 1985 PAGE 2 Staff has again surfaced this concern during the review and approval process of Tentative Map No. 85-246 and request that it be considered as a condition of approval of said maps. The attached drawing generally delineates the requested modifications. This modification provides for an enlarged turning radius at the corner with the skewed approach angle (45°), the channelization island is enlarged to reduce the wide open appearance of the intersection and an acceleration/merge area is shown to provide smoother transition of the free right turning Main St. traffic into the southbound Newport Ave. traffic. This drawing also shows the estimated loss of building area (1,460 sq. ft.) shaded in blue. This drawing also shows that there will be no loss of parking spaces as previously indicated by the developer. Carver Developments consultants have indicated that the City's desires could be met by removing parking for a distance along Newport Avenue. This is true in the interim condition where Newport Ave. is stripped for two southbound travel lanes and a parking lane. However, this concept will be unworkable when Newport Ave. is restripped to accommodate three southbound travel lanes and no parking lane. The use of a yield sign, as discussed in the Crain Associates letter, was originally included within the City's modified plan. The City has relinquished the use of approximately 4,200 sq. ft. of land by allowing a five foot wide sidewalk adjacent to the curb along the entire frontage of Newport Ave. and allowing the remaining three feet of public right-of-way to be utilized for landscaping to enhance the development. This three foot wide area will also be utilized for street lights, signing, fire hydrants, etc. Additionally, the Redevelopment Agency is participating in the cost of the public improvements on this project. Consequently, staff does not feel the loss of 1,420 sq. ft. of building area is an unreasonable request to improve future traffic movements. Carver Development has suggested that the modifications not be made at this time, but only if needed in the future. This plan is not workable because in the future, the City would be required to acquire right-of-way (both land and building) at inflated cost and they would be required to make duplicate public improvements since the Redevelopment Agency will be responsible for the interim improvements as proposed by Carver Development. There are additional staff concerns relating to the bike trail width as proposed by the developer and the proposed width of sidewalk along Main St. These items will be addressed in a separate memo. Staff and the City's Traffic Consultant will be available at the September 16th meeting to respond to any questions. Bob Ledendecker Director of Public Works/City Engineer BL: j r AGENDA, SEPTEMBER 9, 1985 DATE: Inter - COIR TO: WILLIAM HUSTON, CITY MANAGER FROM: BOB LEDENDECKER, DIRECTOR OF PUBLIC WORKS/CITY ENGINEER SUBJECT: TENTATIVE PARCEL MAP NO. 85-246 - CARVER DEVELOPMENT SITE PLAN RECOMMENDATION: That the Tustin City Council, at their meeting of September 16, 1985, as a part of their approval of Tentative Map No. 85-246 confirm the following items pertaining to the Carver Development site plan: ° Newport Ave. bike trail shall be 10 ft. in lieu of 8 ft. ° Landscape area between the sidewalk and biketrail along Newport Avenue shall contain only low profile shrubs and ground covers. ° Sidewalk along Main St. shall be 8 ft. wide in lieu of 5 ft. wide. RArVnP 111Nn- In reviewing the finalized site plan for the subject development with respect to the modifications at the southwesterly corner of Main St. and Newport Ave., three additional concerns have surfaced as follows: Newport Ave. bike trail width. Landscaping of three ft. area between bike trail and sidewalk. ° Sidewalk width along Main St. nTSrIICCTnN- During the initial site plan reviews staff has repeatedly indicated that the minimum bike trail width is ten (10) feet. The latest site plan indicates an eight foot wide bike trail. This is unacceptable and will require a change to the site plan. The landscaping between the bike trail and sidewalk should be limited to low profile shrubs and/or ground covers as previously discussed with the developer. This area is primarily reserved for street lights, signing and fire hydrants. The final site plan proposes Palm Trees which are not only impractical in the three foot wide areas, but could be a future displacement problem to the sidewalk and bike trail. The sidewalk, as shown along the Main St. frontage, is five feet wide and adjacent to the curb. This was discussed with the developer and agreed upon when there was a hardship with building setback requirements along Main St. Initially, the developer could not provide the required fifteen foot setback from right-of-way. SEPTEMBER 9, 1985 PAGE 2 It was suggested that the sidewalk be reduced by three feet of the walk, but within the public right-of-way, be utilized landscaping, street lights, fire hydrants, signing, etc. It there is no hardship to maintain the fifteen foot setback as site plan and the normal sidewalk width of eight feet can be Bob Ledendecker Director of Public Works/City Engineer BL: j r and that area in back for additional now appears that shown on the final installed. x Crain & Asscciatcs Of scuthcif <<1111c1nia August 27, 1985 Mr. Stan C. Cole, Vice President Carver Development 17 Corporate Plaza Drive Newport Beach, California 92658-0070 Dear Mr. Cole, 2007 Sawtelle Boulevard, Suite 4 Los Angeles, California 90025 (213) 473-6508 RECEIVE® TUSTIN PUBLIC WORKS DEFT. AUG 2 9 985 ,= BY 1 We have reviewed the geometric plans prepared for your retail/office project in the City of Tustin (Tentative Parcel Map No. 85-246). Particular attention has been given to a review of the projected pedestrian and vehicular (including bicycles) traffic that could occur at the intersection of Newport Avenue and Main Street. With regard to the proposed acceleration lane along Newport Avenue (for traffic turning right from Main Street to southbound Newport Avenue) our review and analysis indicates that the acceleration lane is not warranted and if installed, could create a safety hazard for both pedestrian and vehicular traffic. A summary of our findings is as follows: 1. Traffic volumes on Newport Avenue are low enough so as not to create any significant potential for conflict with the low volumes of right - turn traffic. ' 2. Appropriate control of traffic in this area should be a YIELD or STOP sign. This type of control provides a safer situation for pedestrians/bicycles and allows motorists a more direct and safer observation of the on -coining traffic stream. 3. An accelaration lane, as proposed, could cause over -the -shoulder _ observation problems and concerns for motorists merging into the Newport Avenue traffic stream. In addition, an acceleration lane would tend to increase overall traffic speeds, and cause increased safety Problems for the pedestrians/bicycles crossing the path of the right - turn vehicles. LOS ANGELES LOS ALTOS WASHINGTON D.C. Letter to Ar. Stan C. Cole August 27, 1985 Page Two 4. Parking prohibitions, along Main Street at the approach to Newport Avenue and along the north side of Newport Avenue at the departure from Main Street, can provide additional maneuvering room and minimize conflicts with thru traffic both along Newport Avenue and on Main Street Ntithout additional right-of-way being required). 5. With regard to the turning radius as proposed, the existing plan is appropriate and actually safer for truck operations in that a somewhat larger radius (with an acceleration lane) may cause more of a conflict between right -turning trucks and through traffic. YIELD or STOP control along with a 35 -foot curb radius (as originally proposed) is appropriate for this location. Our analysis and the analysis contained in the Initial Study show that an acceptable Level -of -Service will be maintained at the project site (in particular at Hain Street and Newport Avenue) once .the project is fully developed. We estimate that traffic along Newport Avenue will have an average 25 -second headway (per lane) which is ample for the occasional right -turning vehicle (traffic turning right from Main Street onto Newport Avenue in the study area will have an average headway of approximately 40 seconds _ between vehicles). Given these low design speeds and volumes of traffic, the operational aspects of this situation are most appropriately dealt with in terms of the normal right-of-way between vehicles and pedestrians/bicycles. In our opinion, the suggested acceleration lane should not be implemented. An improvement of this sort could create safety problems and increase accident _ potential. In addition, the proposed curb radius is appropriate when consideration is given to all existing and future traffic flows and to appropriate control measures for this location. If you have additional questions or would like to have us meet with the City Engineer to discuss these issues, we would be more than happy to do so. Sincerely; Dan Barnett, P.E. Senior Partner DB/se 1 1448 DOUR RUG E fl HDHI[S 1 4 4 3 1 HAMLIN STREET VAN N U Y S, CALIFORNIA • 9 1 4 0 1 (818) 785- 1 578 • (21gg3) 87223.1578 A , .utt&7EU1985 Carver Development 17 Corporate Plaza Dr4 ve Newport Beach, California 92660 Attention: Mr. Stan Cole Subject: Gentlemen: AUG 2 8 1985 NEWPORT BEACH Main Street/Newport Avenue File No. 2007-00-00 You have requested an opinion about the existing configur- ation and control of the intersection of Main Street and Newport Avenue. Specifically, you are concerned about the vehicle movement from southeastbound Main Street to south - westbound Newport Avenue. The existing configuration at the infersection includes a turning lane that is separated from the intersection by a triangular island. That configuration is necessary because of the acute angle at which the streets intersect. The present configuration is appropriate. However, because the right -turning movement is not controlled by the signal at the intersection, there shou`Id be a YIELD sign facing that movement. Any additional modifications would be unnecessary. _ Very truly yours, DON D FRI ER 8 ASSOCIATES 1� Donald Frischer, P. E. DF/r a DATE: SEPTEMBER 10, 1985 Inter - Com TO: BOB LEDENDECKER, DIRECTOR OF PUBLIC WORKS/CITY ENGINEER FROM: JIM KAWAMURA, CONSULTING TRAFFIC ENGINEER SUBJECT: CARVER DEVELOPMENT - IMPROVEMENTS TO SOUTHWEST CORNER OF NEWPORT AVENUE/MAIN STREET The subject corner of the proposed development site will require the following improvements to prevent future traffic problems from occurring: 1. The corner turning radius should be increased from approximately 35 feet to 50 feet in order to facilitate the right -turn movement (particularly by commercial trucks) from eastbound Main Street to southbound Newport Avenue. 2. In accordance with the enlarged corner turning radius, a channelizing island should be constructed to lessen the skewed approach angle (45°) to the intersection. 3. The subject right -turn should transition into an expanded acceleration/merge area (approximately 100 feet in length) on Newport Avenue. The above improvements are illustrated on the attached site plan submitted by the developer. Specific reasons for the above improvements are: 1. Existing (1985) average daily traffic (ADT) volumes on Main Street and Newport Avenue are 11,000 vehicles per day and 29,000 vehicles per day, respectively. 2. Various independent studies of traffic and circulation indicate future ADT volumes on Main Street and Newport Avenue will increase dramatically to 24,000 vehicles per day and 47,000 vehicles per day, respectively. 3. The projected increases of 218% and 162% on Main Street and Newport Avenue, respectively, represent traffic volumes well in excess of capacity. Therefore, heavy peak hour congestion may be expected. 4. In 1984, a total of 12 traffic accidents occurred at the subject intersection. Of these, four (or 33%) involved right -turning vehicles from eastbound Main Street to southbound Newport Avenue. (See attached collision diagram). SEPTEMBER 10, 1985 PAGE 2 5. Detailed review of those accidents involving right -turning vehicles revealed the primary causes are driver indecision on whether to complete the right -turn movement or stop, and driver inability to merge with through traffic on Newport Avenue. 6. A cross weaving problem currently exists when left -turning vehicles from southbound Centennial Way try to cut across Main Street traffic to make the right -turn onto southbound Newport Avenue. The proposed improvements will allow future traffic controls (such as the extension of a raised island) to be placed on Centennial Way traffic as related to the subject intersection. Attached, for your information, are relevant excerpts from the CalTrans Planning Manual on the design standards for channelization. These excerpts cover the purpose, principles, and design criteria for channelization such as that recommended for the proposed development. Examples of the subject channelization design may be found throughout Orange County, California, and the Nation. One nearby example is the entrance driveway to the Marriott Hotel in Irvine on Von Karman Avenue. :jr Attachments ' C"LLISION DIAGRAM iTY OF TUSTIN LEGEND -SYMBOLS Moving Vehicle --► Backing Vehicle -E 0 Out of Control Parked Vehicle— Pedestrian ehicle__Pedestrian ---� Fixed Object m Non -Injury O Injury Fatal Daylight L rk p po -LOCATION: ACCIDENT SUMts.ARY TYPE DAY NIGHT 'TOTAL Fatal Ini.1 P.D. Fatal In P.D. Fatal' In . P.D. i2ivht Angle _ Rear En _ Left Turn _ Sideswipe - Pedestrian 6 -ter — - - -- W. /l>pmo.,vAc. Tx,,5- �- Fsgej q Port 7—Design PLANNING MANUAL Channelizcrtion Design Standards (7-405) 7-405.1 General Notes on Channelization (1) Purpose and Uses of Channelization. The ob- ject of c anne 7zatti n is to se arate or regulate con- flicting traffic movements into deftnite paths of travel U�te use of tra a islands, pavement markings or other suitable mean`sfacilitate tTe safe an or er movements of bothve is es an a estrians. anne - zation is the highest degree o intersection develop- ment. It is used on 2 -lane and on both divided and un- divided multilane highways for major intersections at grade and in some cases at minor intersections having a large paved area. (See Figures 7406.2-34-5). Only quadrants of an intersection having warrants for separate turning lanes, speed change lanes or other channelization features should be channelized. For the remaining quadrants, the minimum all -paved design is adequate. (2) Alignment and Profile. Intersections occur- ring on horizontal or crest vertical curves are unde- sirab'*V from the standpoint of operation and sight dis- tan; :. When there is latitude in the selection of inter- section locations, vertical or horizontal curvature should be avoided. A line or grade change is frequently warranted when major intersections are involved. If a curve is unn : oidable, it should be as flat as site conditions permit. Where the grade of the through road is steep, flattening through the intersection area is desirable as a safety measure. (3) Design Standards. The following design standards pertain to design elements of channeliza- tions. "Geometric Design Standards" (Section 7-200) should be followed in the design of ail features of the through highway within the intersectional area. 7-405.2 Sight Distance The minimum stopping sight distance shall be pro- vided on each separate leg or turning lane of an inter- section consis'ent with its respective design speed. An exception is the sight distance to an e; -it nose which should be 1,000 feet. In addition, the maximum ob- tainable intervisibility between vehicles approaching the intersection should be provided. The minimum intery :sibiiity shall be as shown on Figure 7-406.1. 7-405.3 Curvature and Safe Speed The radii given in Table 7-405.3 permit safe opera- tion at the designated turning speeds and supereleva- tion rates. (1) Minimum Curve Radius. For purposes of this manual, the curve radius of a turning lane is the radius of the outside edge of the traveled way as C efined under Index No. 7-405.4. The minimum curve 7-405.1 August, 7964 (2) Curve Radius for Continuous Flow. Designs for continuous flow normally require radii greater than 100 feet since capacity diminishes rapidly as the curve radius decreases, especially when it is less than 100 feet. At signalized intersections, the capacity dur- ing the green interval is similarly reduced for turning traffic. The capacity of a turning lane with a 200 -foot radius is about 30 passenger vehicles per minute or 1200 to 1500 per hour. (3) Use of Standard Radii. The radii given in Table 7-405.3 permit safe operation at the stated turn- ing speeds and superelevation rates. For intermediate radii not given in the table, the turning speed for the nearest lower radius listed shall be used. TABLE 7-405.3 Standards of Curvature for Intersedions Turning speed (Miles per hour)-------- @1 20 25 30 40 50 Minimum curve radius—feet _ - 60 100 125 -200 400 650 Maximum super- — elevation (Percent) __ 12.5 12.5 12 12 74 5.4 Curvature and Lane Width (1) ne Width. For purposes of lane width ' measured as follows: (a) When curbs are used, the width is the width the travels y exclusive of shoulders. (b) When curbs are the curb line is con- sidered the ed of th raveled way. (2) Radii Less T n 200 Feet. ne widths are variable for cu • radii less than 200 t; the width of all turni anes must accommodate commer- cial des ehicle. The out edge of varia a width lanes all be a simple circular curve ; the inn edge shkiT be a three -center compound curve. Part 7—Design PLANNING MANUAL 7-402.3 August, 1964 are proposed, the method of phasing is always re- quired. When pedestrian traffic volrunes are sufficient to affect the design, complete information on present and future movements is necessary. 7-402.3 Site Topography Site topography may be obtained from aerial photo- graphs, ground surveys or topographic snaps. A scale of 1" — 50' is preferred. Site topography shall include all improvements and physical controls within the area that may be affected by the design. The use and type of existing improvements are necessary aids in deter - elinin". access requirements. Profiles of the intersect- ing roadways are essential. 7-402.4 Accident Data Complete accident data and analysis are essential for redesign of existing intersections. This informa- tion is normally furnished by the Traffic Department. 7-402.5 Right of Way Controls Cost estimates of right of way parcels which may be affected by alternate designs are essential. Right of wav cost data are normally obtained from the Right of AVay Department. Principles of C'hannelization (7-403) 7-403.1 Preference to Major Movements The provision of direct free-flowing high -standard alignment to give preference to major movements is good channelization practice. This may require some degree of control of the minor movements such as stopping, bending, funnelin1p, or even eliminating them. These controlling ineasures should conform to natural paths of movement and should be introduced gradually to eliminate any element of surprise. 7-403.5 Areas of Conflict Lame all -Raved intersectional a desirable. The hazards of con is come magnified due to contusion and the inability of drivers to anticipate movements of other vehicles within these areas. Channelization reduces areas o into definite oaths of travel by the usP of navement 7.ar a areas of intersectional conflict are character- ist)c of skewed intersection ani Ps. ierefore redue- tion of angle of intersection is a material aid in reduc- ing conflict areas. 7-403.3 Angle of intersection A right-angle intersection provides the shortest crossing distance for intersecting traffic streams. It also provides the most favorable condition for drivers to judge the relative position and speed of intersecting vehicles. Intersection -angles skewed not more than 30 degrees from a right angle do not materially increase crossing distances or decrease visibility unrea onabl.•, and are therefore considered satisfactory. When intersection angles are skewed more than 30 degrees from a rig t angle, the subordinate leg7f the intersection may be realigned if warranted y traffie and economic conal era ions. 7-403.4 Points of Conflict Channelization separates and clearly defines points of conflict within the intersection. Drivers are then exposed to only one conflict and con rontec wit n one decision at a time. 7-403.5 Speed -change Areas The provision of speed -chane areas_ for vehic entering oreavin� main streams of traffic is essent to the safety and P (.iPnev of qn intarcartinn nt 11W Tramc mer es most etticlently with through traffic when the merging angle is sins — and wlien speed differentials s tire at a minlmunlAeePlPrat_in„ nr merging lanes tneretore must be at least Ion" enough for merging traffic to attain the average snee of Speed -change areas for diverging traffic should pro- vide adequate length clear, f the t route 1 lanesto permit vehicles to decelerate tote sa a speed of the != Urate turnii7g lanes after leaving the through lane.; _&t the average speed.of the tbroujrh traffic. 7-403.6 Turning Traffic A separate turning lane permits segregation of traffic movements all(] removes turning movements from the intersectional area. Abrupt reduction of align- ment and sight distance standards should be avoided, particularly where traffic turns into a separate turn- ing lane from a high -standard through facility. 7-403.7 Funneling It is generall,v desirable to re -elate subordinate traffic moyements to a "Male an, %vhere Lhev enter or lease a movinn traffic stream. The mouth of a separate turning lane should e flareZI or -widened to afford cast' entrance and then funneled or narrowed to permit regulation to a single lane. If proper].• desi-ned, fun- neling discourages undesirable overtaking and passing in a conflict area. Funneling must be made readily ap- parent to the driver. 7-403.8 Refuge Areas The shadowiii effect of traffic islands may be used to provide refuge areas for turning and crossing vehicles. Agate s a owing provides safe refug' for a vehicle river waiting or an opportunity to cross or enter an uncontrolled tattie s ream.. 11nian- nellzation also may provide for a safer crossing of two Part 7—Design PLANNING MANUAL or more traffic streams by permitting driers to select a safe time gap in one traffic stream at a time. Traffic islands also may serve the same purposes_ for pe estrians. 7-403.9 Prohibited Turns Traffic islands may be em loved to divert traffic streams in7esired directions and prevent- s ecl c un- esira a movements. 7-403.10 Effective Signal Control At intersections with complex turning movements, channelization is required for effective signal control. Channelization permits the sorting of approaching traffic which may move through the to ersectionur- tn se arate signal ases, This requirement is of par- t u ar importance wlien tra a-actua a signs con- trols are employed. 7-403.11 Installation of Traffic Control Devices Channelization may provide locations for the instal- lation of essential traffic control devices, such as stop and directional signs. Traffic islands constructed solely for this purpose should be carefully designed in order that they do not become a built-in hazard. 7-403.9 March 14, 1968 7-403.12 Summary In the application of the principles of channeliza- tion, judgment must be exercised in order that traffic islands designed to separate and regulate traffic move- ments do not introduce confusion due to complexity or become punitive due to excessive restriction. These precautions are particularly important in rural or high-speed areas. Complex intersections presenting multiple choice of movement are undesirable. Simplicity is a desirable goal in all channelization design. Since most traffic islands are provided only to de- fine and regulate traffic movements, these islands should be traversable in case of an emergency. Islands bordering high-speed through lanes should generally be kept clear of the shoulder areas. Barrier curbs gen- erally can be justified only where protection of pe- destrians is a primary consideration. Safety should be given careful consideration in all channelization. In the redesign of existing inter c- tions n ersec- tions an analysis of past accident experience will es- tablish a pattern which will provide a valuable guide as to the amount and type of channelization required. Intersection Design Procedures (7-404) 7-404.1 Major Design Steps i_ (1) Basic Data. Prepare or obtain all basic data relative to traffic, physical and economic factors as dis- cussed under Topic No. 7402. (2) Preliminary Designs. Using aerial photo- graphs, base maps (hard copy) or topographic maps as a base, prepare preliminary sketches of the general plan and profiles for alternative designs that are adapted to conditions. (3) Comparative Costs. Prepare cost estimates of alternative designs. (4) Selection of Most Suitable Design. Select the most suitable design from the standpoint of traffic ade- quacy and economy. (5) Final Plans. Hake the necessary calculations for lines and grades and complete the final plans. 7-404.2 Approval Headquarters Engineer of Design approval of inter- section at grade is delegated to the District Re- viewers. The review and approval will normally be accomplished in the District. Figure 7-406.6 " I . i August, 1964 U I a W a W a Figure 7-406.6 " I . i August, 1964 J D II "l W I. Ia o of o n ac W W a UiI !: U' I W a 2 Ir ail N r I 1 S ...... . .: _I rt ,w..... 3 �_�_----�— N �cr o i o= a o f ( I crab a¢W i f F I I 0 N Zcr J W N mF ZII a a z ....... J D II i Figure 7-405.7 August, 1964 I 24' �► ' offset Edge of Pavement TurningRodius plus 2N. \ ( Set Ind es No. 7-405.6 1 LARGE ISLANDS s` offset SHC —ING PARABOLIC FLARE J�ote I I - AT NOSE Minimum radius at island points - I Ft. I t a 24 y . Ede of Pavement 9-00 �- shoulder un.� \ � 1 ISLAND TOO SHORT �; FOR PARABOLIC FLARE ��'