Lead pilot of a warbird formation flight in washington dc reported he deviated from assigned altitud...

Attributes
ACN	1263095
Time
Date	201505
Local Time Of Day	1201-1800
Place
Locale Reference	PCT.TRACON
State Reference	VA
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Make Model Name	Small Aircraft Low Wing 1 Eng Retractable Gear
Operating Under FAR Part	Part 91
Flight Phase	Initial Approach Cruise
Route In Use	Visual Approach Vectors
Flight Plan	SVFR
Aircraft 2
Make Model Name	Medium Large Transport
Operating Under FAR Part	Part 91
Flight Phase	Cruise
Person 1
Function	Pilot Flying Single Pilot
Qualification	Flight Crew Commercial Flight Crew Instrument
Experience	Flight Crew Last 90 Days 45 Flight Crew Total 1600 Flight Crew Type 265
Events
Anomaly	Deviation - Altitude Excursion From Assigned Altitude Deviation - Procedural Clearance Inflight Event / Encounter Bird / Animal Inflight Event / Encounter Wake Vortex Encounter
Miss Distance	Horizontal 2 Vertical 2

Narrative:

Leading a 4-ship [formation flight] through the washington; dc sfra. Between wake turbulence and concern for birds the flight's altitude dropped below that prescribed in the briefing. Speed issues also were challenging due to the vectoring and instructions from potomac TRACON. These type of aircraft; [are] a sleek and slick platform that does not have speed brakes. Further; rapid and random power changes are not recommended for engine safety and to maintain the integrity of the formation. Power reductions need to be done gradually for engine care and operation and they need to be done even more carefully when managing a formation flight where three other aircraft are all reading off of the lead airplane. In short; consideration of the safety of the formation priority number one; making rapid changes would have been difficult and unsafe. The spacing and recommended speed changes made by TRACON required our 4-ship [formation] to encounter wake turbulence behind [other aircraft] prior to our entering of the airspace. The altitude factors were not only wake-turbulence; specifically hawks and other bird life operating at and above the briefing altitude and the lead pilot made a command decision to be at the safe or lower than briefed altitude. Our 4-ship encountered numerous potential bird strikes at the briefing altitude on the inbound portion of the flight. Safe operation of the flight required the lead pilot to descend below briefed minimum to avoid wake turbulence and wildlife. The problem was further enhanced by known photo ship aircraft; creating additional safety concerns in keeping with safe distance. Judgment was used in keeping ample speed and safe altitude to maintain flight path. At no time was the flight path deviated; but altitude and speed were used to maintain safe flight operations; formation integrity and safe flight.

Original NASA ASRS Text

Title: Lead pilot of a warbird formation flight in Washington DC reported he deviated from assigned altitude because of concerns for wake turbulence and bird encounters.

Narrative: Leading a 4-ship [formation flight] through the Washington; DC SFRA. Between wake turbulence and concern for birds the flight's altitude dropped below that prescribed in the briefing. Speed issues also were challenging due to the vectoring and instructions from Potomac TRACON. These type of aircraft; [are] a sleek and slick platform that does not have speed brakes. Further; rapid and random power changes are not recommended for engine safety and to maintain the integrity of the formation. Power reductions need to be done gradually for engine care and operation and they need to be done even more carefully when managing a formation flight where three other aircraft are all reading off of the lead airplane. In short; consideration of the safety of the formation priority number one; making rapid changes would have been difficult and unsafe. The spacing and recommended speed changes made by TRACON required our 4-ship [formation] to encounter wake turbulence behind [other aircraft] prior to our entering of the airspace. The altitude factors were not only wake-turbulence; specifically hawks and other bird life operating at and above the briefing altitude and the lead pilot made a command decision to be at the safe or lower than briefed altitude. Our 4-ship encountered numerous potential bird strikes at the briefing altitude on the inbound portion of the flight. Safe operation of the flight required the lead pilot to descend below briefed minimum to avoid wake turbulence and wildlife. The problem was further enhanced by known photo ship aircraft; creating additional safety concerns in keeping with safe distance. Judgment was used in keeping ample speed and safe altitude to maintain flight path. At no time was the flight path deviated; but altitude and speed were used to maintain safe flight operations; formation integrity and safe flight.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

Lead pilot of a warbird formation flight in washington dc reported he deviated from assigned altitude because of concerns for wake turbulence and bird encounters.